Merge pull request #1515 from TASVideos/interp_emuhawk

Use string interpolation in BizHawk.Client.EmuHawk

BizHawk.Client.EmuHawk/AVOut/AviWriter.cs

@@ -53,7 +53,7 @@ namespace BizHawk.Client.EmuHawk
 			int counter = 1;
 			for (;;)
 			{
-				yield return Path.Combine(dir, baseName) + "_" + counter + ext;
+				yield return Path.Combine(dir, $"{baseName}_{counter}{ext}");
 				counter++;
 			}
 		}
@@ -97,7 +97,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch (Exception e)
 			{
-				MessageBox.Show("AVIFIL32 Thread died:\n\n" + e);
+				MessageBox.Show($"AVIFIL32 Thread died:\n\n{e}");
 			}
 		}
 
@@ -321,10 +321,10 @@ namespace BizHawk.Client.EmuHawk
 				int bytes = 0;
 				if (a_bits == 16) bytes = 2;
 				else if (a_bits == 8) bytes = 1;
-				else throw new InvalidOperationException("only 8/16 bits audio are supported by AviWriter and you chose: " + a_bits);
+				else throw new InvalidOperationException($"only 8/16 bits audio are supported by AviWriter and you chose: {a_bits}");
 				if (a_channels == 1) { }
 				else if (a_channels == 2) { }
-				else throw new InvalidOperationException("only 1/2 channels audio are supported by AviWriter and you chose: " + a_channels);
+				else throw new InvalidOperationException($"only 1/2 channels audio are supported by AviWriter and you chose: {a_channels}");
 
 				wfex.Init();
 				wfex.nBlockAlign = (ushort)(bytes * a_channels);
@@ -648,7 +648,7 @@ namespace BizHawk.Client.EmuHawk
 
 				if (Win32.FAILED(Win32.AVIFileOpenW(ref pAviFile, destPath, Win32.OpenFileStyle.OF_CREATE | Win32.OpenFileStyle.OF_WRITE, 0)))
 				{
-					throw new InvalidOperationException("Couldnt open dest path for avi file: " + destPath);
+					throw new InvalidOperationException($"Couldnt open dest path for avi file: {destPath}");
 				}
 
 				// initialize the video stream
@@ -991,7 +991,7 @@ namespace BizHawk.Client.EmuHawk
 //        using (Font f = new Font(FontFamily.GenericMonospace, 10))
 //            g.DrawString(i.ToString(), f, Brushes.Black, 0, 0);
 //    }
-//    //bmp.Save(string.Format("c:\\dump\\{0}.bmp", i), ImageFormat.Bmp);
+//    //bmp.Save($"c:\\dump\\{i}.bmp", ImageFormat.Bmp);
 //    for (int y = 0, idx = 0; y < 256; y++)
 //        for (int x = 0; x < 256; x++)
 //            video.buffer[idx++] = bmp.GetPixel(x, y).ToArgb();

BizHawk.Client.EmuHawk/AVOut/FFmpegWriter.cs

@@ -91,8 +91,7 @@ namespace BizHawk.Client.EmuHawk
 				ffmpeg.StartInfo.FileName = "ffmpeg"; // expecting native version to be in path
 #endif
 
-				string filename = _baseName + (_segment > 0 ? $"_{_segment}" : "") + _ext;
+				_ffmpeg.StartInfo.Arguments = $"-y -f nut -i - {_token.Commandline} \"{_baseName}{(_segment == 0 ? string.Empty : $"_{_segment}")}{_ext}\"";
-				_ffmpeg.StartInfo.Arguments = string.Format("-y -f nut -i - {1} \"{0}\"", filename, _token.Commandline);
 				_ffmpeg.StartInfo.CreateNoWindow = true;
 
 				// ffmpeg sends informative display to stderr, and nothing to stdout
@@ -100,7 +99,7 @@ namespace BizHawk.Client.EmuHawk
 				_ffmpeg.StartInfo.RedirectStandardInput = true;
 				_ffmpeg.StartInfo.UseShellExecute = false;
 
-				_commandline = "ffmpeg " + _ffmpeg.StartInfo.Arguments;
+				_commandline = $"ffmpeg {_ffmpeg.StartInfo.Arguments}";
 
 				_ffmpeg.ErrorDataReceived += new DataReceivedEventHandler(StderrHandler);
 
@@ -132,7 +131,7 @@ namespace BizHawk.Client.EmuHawk
 					_stderr.Dequeue();
 				}
 
-				_stderr.Enqueue(line.Data + "\n");
+				_stderr.Enqueue($"{line.Data}\n");
 			}
 		}
 
@@ -193,7 +192,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (_ffmpeg.HasExited)
 			{
-				throw new Exception("unexpected ffmpeg death:\n" + ffmpeg_geterror());
+				throw new Exception($"unexpected ffmpeg death:\n{ffmpeg_geterror()}");
 			}
 
 			var video = source.GetVideoBuffer();
@@ -203,7 +202,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch
 			{
-				MessageBox.Show("Exception! ffmpeg history:\n" + ffmpeg_geterror());
+				MessageBox.Show($"Exception! ffmpeg history:\n{ffmpeg_geterror()}");
 				throw;
 			}
 
@@ -274,7 +273,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (_ffmpeg.HasExited)
 			{
-				throw new Exception("unexpected ffmpeg death:\n" + ffmpeg_geterror());
+				throw new Exception($"unexpected ffmpeg death:\n{ffmpeg_geterror()}");
 			}
 
 			if (samples.Length == 0)
@@ -289,7 +288,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch
 			{
-				MessageBox.Show("Exception! ffmpeg history:\n" + ffmpeg_geterror());
+				MessageBox.Show($"Exception! ffmpeg history:\n{ffmpeg_geterror()}");
 				throw;
 			}
 		}

BizHawk.Client.EmuHawk/AVOut/FFmpegWriterForm.cs

@@ -142,7 +142,7 @@ namespace BizHawk.Client.EmuHawk
 			if (listBox1.SelectedIndex != -1)
 			{
 				var f = (FormatPreset)listBox1.SelectedItem;
-				label5.Text = "Extension: " + f.Extension;
+				label5.Text = $"Extension: {f.Extension}";
 				label3.Text = f.Desc;
 				textBox1.Text = f.Commandline;
 			}

BizHawk.Client.EmuHawk/AVOut/ImageSequenceWriter.cs

@@ -45,9 +45,7 @@ namespace BizHawk.Client.EmuHawk
 		public void AddFrame(IVideoProvider source)
 		{
 			string ext = Path.GetExtension(_baseName);
-			string name = Path.GetFileNameWithoutExtension(_baseName) + "_" + _frame;
+			var name = Path.Combine(Path.GetDirectoryName(_baseName), $"{Path.GetFileNameWithoutExtension(_baseName)}_{_frame}{ext}");
-			name += ext;
-			name = Path.Combine(Path.GetDirectoryName(_baseName), name);
 			BitmapBuffer bb = new BitmapBuffer(source.BufferWidth, source.BufferHeight, source.GetVideoBuffer());
 			using (var bmp = bb.ToSysdrawingBitmap())
 			{

BizHawk.Client.EmuHawk/AVOut/JMDWriter.cs

@@ -671,7 +671,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch (Exception e)
 			{
-				System.Windows.Forms.MessageBox.Show("JMD Worker Thread died:\n\n" + e);
+				System.Windows.Forms.MessageBox.Show($"JMD Worker Thread died:\n\n{e}");
 				return;
 			}
 		}

BizHawk.Client.EmuHawk/AVOut/NutMuxer.cs

@@ -592,7 +592,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				dest.Write(data, 0, actual_length);
 				_pool.ReleaseBuffer(data);
-				//dbg.WriteLine(string.Format("{0},{1},{2}", pts, ptsnum, ptsden));
+				//dbg.WriteLine($"{pts},{ptsnum},{ptsden}");
 			}
 		}
 

BizHawk.Client.EmuHawk/AVOut/SynclessRecorder.cs

@@ -38,11 +38,11 @@ namespace BizHawk.Client.EmuHawk
 			mProjectFile = projFile;
 			mBaseDirectory = Path.GetDirectoryName(mProjectFile);
 			string basename = Path.GetFileNameWithoutExtension(projFile);
-			string framesDirFragment = basename + "_frames";
+			string framesDirFragment = $"{basename}_frames";
 			mFramesDirectory = Path.Combine(mBaseDirectory, framesDirFragment);
 			StringBuilder sb = new StringBuilder();
 			sb.AppendLine("version=1");
-			sb.AppendLine("framesdir=" + framesDirFragment);
+			sb.AppendLine($"framesdir={framesDirFragment}");
 			File.WriteAllText(mProjectFile, sb.ToString());
 		}
 
@@ -55,7 +55,7 @@ namespace BizHawk.Client.EmuHawk
 			using (var bb = new BitmapBuffer(source.BufferWidth, source.BufferHeight, source.GetVideoBuffer()))
 			{
 				string subpath = GetAndCreatePathForFrameNum(mCurrFrame);
-				string path = subpath + ".png";
+				string path = $"{subpath}.png";
 				bb.ToSysdrawingBitmap().Save(path, System.Drawing.Imaging.ImageFormat.Png);
 			}
 		}
@@ -63,7 +63,7 @@ namespace BizHawk.Client.EmuHawk
 		public void AddSamples(short[] samples)
 		{
 			string subpath = GetAndCreatePathForFrameNum(mCurrFrame);
-			string path = subpath + ".wav";
+			string path = $"{subpath}.wav";
 			WavWriterV wwv = new WavWriterV();
 			wwv.SetAudioParameters(paramSampleRate, paramChannels, paramBits);
 			wwv.OpenFile(path);
@@ -149,7 +149,7 @@ namespace BizHawk.Client.EmuHawk
 			string subpath = GetPathFragmentForFrameNum(index);
 			string path = mFramesDirectory;
 			path = Path.Combine(path, subpath);
-			string fpath = path + ".nothing";
+			string fpath = $"{path}.nothing";
 			Directory.CreateDirectory(Path.GetDirectoryName(fpath));
 			return path;
 		}

BizHawk.Client.EmuHawk/AVOut/SynclessRecordingTools.cs

@@ -21,8 +21,8 @@ namespace BizHawk.Client.EmuHawk
 			string subpath = SynclessRecorder.GetPathFragmentForFrameNum(index);
 			string path = mFramesDirectory;
 			path = Path.Combine(path, subpath);
-			png = path + ".png";
+			png = $"{path}.png";
-			wav = path + ".wav";
+			wav = $"{path}.wav";
 		}
 
 		private string mSynclessConfigFile;
@@ -32,7 +32,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var ofd = new OpenFileDialog
 			{
-				FileName = PathManager.FilesystemSafeName(Global.Game) + ".syncless.txt",
+				FileName = $"{PathManager.FilesystemSafeName(Global.Game)}.syncless.txt",
 				InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries.AvPathFragment, null)
 			};
 

BizHawk.Client.EmuHawk/AVOut/WavWriter.cs

@@ -265,7 +265,7 @@ namespace BizHawk.Client.EmuHawk
 			int counter = 1;
 			while (true)
 			{
-				yield return new FileStream(Path.Combine(dir, baseName) + "_" + counter + ext, FileMode.Create);
+				yield return new FileStream($"{Path.Combine(dir, baseName)}_{counter}{ext}", FileMode.Create);
 				counter++;
 			}
 		}

BizHawk.Client.EmuHawk/AboutBox.cs

@@ -163,9 +163,9 @@ namespace BizHawk.Client.EmuHawk
 		private void AboutBox_Load(object sender, EventArgs e)
 		{
 #if DEBUG
-					Text = "BizHawk Developer Build (DEBUG MODE) GIT " + SubWCRev.GIT_BRANCH + "#" + SubWCRev.GIT_SHORTHASH;
+					Text = $"BizHawk Developer Build (DEBUG MODE) GIT {SubWCRev.GIT_BRANCH}#{SubWCRev.GIT_SHORTHASH}";
 #else
-			Text = "BizHawk Developer Build (RELEASE MODE) GIT " + SubWCRev.GIT_BRANCH + "#" + SubWCRev.GIT_SHORTHASH;
+			Text = $"BizHawk Developer Build (RELEASE MODE) GIT {SubWCRev.GIT_BRANCH}#{SubWCRev.GIT_SHORTHASH}";
 #endif
 					if (DateTime.Now.Month == 12)
 				if (DateTime.Now.Day > 17 && DateTime.Now.Day <= 25)

BizHawk.Client.EmuHawk/Api/Libraries/CommApi.cs

@@ -33,7 +33,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public string SocketServerSend(string SendString)
 		{
-			return "Sent : " + GlobalWin.socketServer.SendString(SendString).ToString() + " bytes";
+			return $"Sent : {GlobalWin.socketServer.SendString(SendString)} bytes";
 		}
 		public string SocketServerResponse()
 		{

BizHawk.Client.EmuHawk/Api/Libraries/GuiApi.cs

@@ -303,7 +303,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (!File.Exists(path))
 					{
-						AddMessage("File not found: " + path);
+						AddMessage($"File not found: {path}");
 						return;
 					}
 
@@ -331,7 +331,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				Console.WriteLine("File not found: " + path);
+				Console.WriteLine($"File not found: {path}");
 				return;
 			}
 
@@ -371,7 +371,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				Console.WriteLine("File not found: " + path);
+				Console.WriteLine($"File not found: {path}");
 				return;
 			}
 

BizHawk.Client.EmuHawk/Api/Libraries/SaveStateAPI.cs

@@ -27,7 +27,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (slotNum >= 0 && slotNum <= 9)
 			{
-				GlobalWin.MainForm.LoadQuickSave("QuickSave" + slotNum, true);
+				GlobalWin.MainForm.LoadQuickSave($"QuickSave{slotNum}", true);
 			}
 		}
 
@@ -40,7 +40,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (slotNum >= 0 && slotNum <= 9)
 			{
-				GlobalWin.MainForm.SaveQuickSave("QuickSave" + slotNum);
+				GlobalWin.MainForm.SaveQuickSave($"QuickSave{slotNum}");
 			}
 		}
 	}

BizHawk.Client.EmuHawk/ArchiveChooser.cs

@@ -145,8 +145,8 @@ namespace BizHawk.Client.EmuHawk
 				errMsg = errMsg.Substring(errMsg.IndexOf('-') + 2);
 
 				// Balloon is bugged on first invocation
-				errorBalloon.Show("Error parsing RegEx: " + errMsg, tb);
+				errorBalloon.Show($"Error parsing RegEx: {errMsg}", tb);
-				errorBalloon.Show("Error parsing RegEx: " + errMsg, tb);
+				errorBalloon.Show($"Error parsing RegEx: {errMsg}", tb);
 			}
 		}
 

BizHawk.Client.EmuHawk/BizBox.cs

@@ -31,14 +31,14 @@ namespace BizHawk.Client.EmuHawk
 				mainversion += " (x64)";
 			if (VersionInfo.DeveloperBuild)
 			{
-				Text = " BizHawk  (GIT " + SubWCRev.GIT_BRANCH + "#" + SubWCRev.GIT_SHORTHASH + ")";
+				Text = $" BizHawk  (GIT {SubWCRev.GIT_BRANCH}#{SubWCRev.GIT_SHORTHASH})";
 			}
 			else
 			{
-				Text = "Version " + mainversion + " (GIT " + SubWCRev.GIT_BRANCH + "#" + SubWCRev.GIT_SHORTHASH + ")";
+				Text = $"Version {mainversion} (GIT {SubWCRev.GIT_BRANCH}#{SubWCRev.GIT_SHORTHASH})";
 			}
 
-			VersionLabel.Text = "Version " + mainversion;
+			VersionLabel.Text = $"Version {mainversion}";
 			DateLabel.Text = VersionInfo.RELEASEDATE;
 
 			var cores = Assembly
@@ -59,12 +59,12 @@ namespace BizHawk.Client.EmuHawk
 				});
 			}
 
-			linkLabel2.Text = "Commit # " + SubWCRev.GIT_SHORTHASH;
+			linkLabel2.Text = $"Commit # {SubWCRev.GIT_SHORTHASH}";
 		}
 
 		private void linkLabel2_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
 		{
-			System.Diagnostics.Process.Start("https://github.com/TASVideos/BizHawk/commit/" + SubWCRev.GIT_SHORTHASH);
+			System.Diagnostics.Process.Start($"https://github.com/TASVideos/BizHawk/commit/{SubWCRev.GIT_SHORTHASH}");
 		}
 
 		private void btnCopyHash_Click(object sender, EventArgs e)

BizHawk.Client.EmuHawk/BizBoxInfoControl.cs

@@ -22,7 +22,7 @@ namespace BizHawk.Client.EmuHawk
 			
 			if (!string.IsNullOrEmpty(attributes.Author))
 			{ 
-				CoreAuthorLabel.Text = "authors: " + attributes.Author;
+				CoreAuthorLabel.Text = $"authors: {attributes.Author}";
 			}
 			else
 			{

BizHawk.Client.EmuHawk/CoreFeatureAnalysis.cs

@@ -229,10 +229,7 @@ namespace BizHawk.Client.EmuHawk
 				.ThenBy(t => t.CoreAttributes.CoreName)
 				.ToList();
 
-			toolStripStatusLabel1.Text = string.Format("Total: {0} Released: {1} Profiled: {2}",
+			toolStripStatusLabel1.Text = $"Total: {possiblecoretypes.Count} Released: {KnownCores.Values.Count(c => c.Released)} Profiled: {KnownCores.Count}";
-				possiblecoretypes.Count,
-				KnownCores.Values.Count(c => c.Released),
-				KnownCores.Count);
 
 			CoreTree.Nodes.Clear();
 			CoreTree.BeginUpdate();

BizHawk.Client.EmuHawk/CustomControls/HexTextBox.cs

@@ -36,7 +36,7 @@ namespace BizHawk.Client.EmuHawk
 			_maxSize = domainSize - 1;
 
 			MaxLength = _maxSize.Value.NumHexDigits();
-			_addressFormatStr = "{0:X" + MaxLength + "}";
+			_addressFormatStr = $"{{0:X{MaxLength}}}";
 
 			//try to preserve the old value, as best we can
 			if(!wasMaxSizeSet)

BizHawk.Client.EmuHawk/CustomControls/TasListView.cs

@@ -14,7 +14,7 @@ namespace BizHawk.Client.EmuHawk
 			// Convenience hack
 			public override string ToString()
 			{
-				return string.IsNullOrEmpty(Column) ? "?" : Column + " - " + (RowIndex.HasValue ? RowIndex.ToString() : "?");
+				return string.IsNullOrEmpty(Column) ? "?" : $"{Column} - {(RowIndex.HasValue ? RowIndex.ToString() : "?")}";
 			}
 		}
 

BizHawk.Client.EmuHawk/CustomControls/VirtualListView.cs

@@ -505,7 +505,7 @@ namespace BizHawk.Client.EmuHawk
 			} 
 			catch (Exception ex) 
 			{
-				System.Diagnostics.Trace.WriteLine("VirtualListView.SetItemState error=" + ex.Message);
+				System.Diagnostics.Trace.WriteLine($"VirtualListView.SetItemState error={ex.Message}");
 				
 				// TODO: should this eat any exceptions?
 				throw;
@@ -551,7 +551,7 @@ namespace BizHawk.Client.EmuHawk
 						}
 						catch (Exception e)
 						{
-							Debug.WriteLine("Failed to copy text name from client: " + e, "VirtualListView.OnDispInfoNotice");
+							Debug.WriteLine($"Failed to copy text name from client: {e}", "VirtualListView.OnDispInfoNotice");
 						}
 					}
 				}
@@ -687,7 +687,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				catch (Exception ex)
 				{
-					Trace.WriteLine(string.Format("Message {0} caused an exception: {1}", m, ex.Message));
+					Trace.WriteLine($"Message {m} caused an exception: {ex.Message}");
 				}
 			}
 		}
@@ -705,7 +705,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (item == null) 
 			{
-				throw new ArgumentException("cannot find item " + idx + " via QueryItem event");
+				throw new ArgumentException($"cannot find item {idx} via QueryItem event");
 			}
 
 			return item;

BizHawk.Client.EmuHawk/CustomControls/Win32.cs

@@ -146,7 +146,7 @@ namespace BizHawk.Client.EmuHawk
 
 			public override string ToString()
 			{
-				return "{Left: " + _Left + "; " + "Top: " + _Top + "; Right: " + _Right + "; Bottom: " + _Bottom + "}";
+				return $"{{Left: {_Left}; Top: {_Top}; Right: {_Right}; Bottom: {_Bottom}}}";
 			}
 
 			public override int GetHashCode()

BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs

@@ -306,7 +306,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				var pass = retroChain.Passes[i];
 				var rsp = new Filters.RetroShaderPass(retroChain, i);
-				string fname = string.Format("{0}[{1}]", name, i);
+				string fname = $"{name}[{i}]";
 				program.AddFilter(rsp, fname);
 				rsp.Parameters = properties;
 			}
@@ -491,7 +491,7 @@ namespace BizHawk.Client.EmuHawk
 			bufferWidth += padding.Horizontal;
 			bufferHeight += padding.Vertical;
 
-			//Console.WriteLine("DISPZOOM " + zoom); //test
+			//Console.WriteLine($"DISPZOOM {zoom}"); //test
 
 			//old stuff
 			var fvp = new FakeVideoProvider();
@@ -915,7 +915,7 @@ namespace BizHawk.Client.EmuHawk
 		public DisplaySurface LockLuaSurface(string name, bool clear=true)
 		{
 			if (MapNameToLuaSurface.ContainsKey(name))
-				throw new InvalidOperationException("Lua surface is already locked: " + name);
+				throw new InvalidOperationException($"Lua surface is already locked: {name}");
 
 			SwappableDisplaySurfaceSet sdss;
 			if (!LuaSurfaceSets.TryGetValue(name, out sdss))
@@ -939,7 +939,7 @@ namespace BizHawk.Client.EmuHawk
 				height += GameExtraPadding.Vertical;
 			}
 			else if(name == "native") { width = currNativeWidth; height = currNativeHeight; }
-			else throw new InvalidOperationException("Unknown lua surface name: " +name);
+			else throw new InvalidOperationException($"Unknown lua surface name: {name}");
 
 			DisplaySurface ret = sdss.AllocateSurface(width, height, clear);
 			MapNameToLuaSurface[name] = ret;

BizHawk.Client.EmuHawk/DisplayManager/FilterManager.cs

@@ -138,11 +138,11 @@ namespace BizHawk.Client.EmuHawk.FilterManager
 			public override string ToString()
 			{
 				if (Type == ProgramStepType.Run)
-					return string.Format("Run {0} ({1})", (int)Args, Comment);
+					return $"Run {(int)Args} ({Comment})";
 				if (Type == ProgramStepType.NewTarget)
-					return string.Format("NewTarget {0}", (Size)Args);
+					return $"NewTarget {(Size)Args}";
 				if (Type == ProgramStepType.FinalTarget)
-					return string.Format("FinalTarget");
+					return "FinalTarget";
 				return null;
 			}
 		}

BizHawk.Client.EmuHawk/DisplayManager/Filters/Retro.cs

@@ -69,7 +69,7 @@ namespace BizHawk.Client.EmuHawk.Filters
 				Shaders[i] = shader;
 				if (!shader.Available)
 				{
-					Errors += string.Format("===================\r\nPass {0}:\r\n{1}",i,shader.Errors);
+					Errors += $"===================\r\nPass {i}:\r\n{shader.Errors}";
 					ok = false;
 				}
 			}
@@ -141,25 +141,25 @@ namespace BizHawk.Client.EmuHawk.Filters
 				sp.Index = i;
 				Passes.Add(sp);
 
-				sp.InputFilterLinear = FetchBool(dict, "filter_linear" + i, false); //Should this value not be defined, the filtering option is implementation defined.
+				sp.InputFilterLinear = FetchBool(dict, $"filter_linear{i}", false); //Should this value not be defined, the filtering option is implementation defined.
-				sp.OuputFloat = FetchBool(dict, "float_framebuffer" + i, false);
+				sp.OuputFloat = FetchBool(dict, $"float_framebuffer{i}", false);
-				sp.FrameCountMod = FetchInt(dict, "frame_count_mod" + i, 1);
+				sp.FrameCountMod = FetchInt(dict, $"frame_count_mod{i}", 1);
-				sp.ShaderPath = FetchString(dict, "shader" + i, "?"); //todo - change extension to .cg for better compatibility? just change .cg to .glsl transparently at last second?
+				sp.ShaderPath = FetchString(dict, $"shader{i}", "?"); //todo - change extension to .cg for better compatibility? just change .cg to .glsl transparently at last second?
 
 				//If no scale type is assumed, it is assumed that it is set to "source" with scaleN set to 1.0.
 				//It is possible to set scale_type_xN and scale_type_yN to specialize the scaling type in either direction. scale_typeN however overrides both of these.
-				sp.ScaleTypeX = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, "scale_type_x" + i, "Source"), true);
+				sp.ScaleTypeX = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, $"scale_type_x{i}", "Source"), true);
-				sp.ScaleTypeY = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, "scale_type_y" + i, "Source"), true);
+				sp.ScaleTypeY = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, $"scale_type_y{i}", "Source"), true);
-				ScaleType st = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, "scale_type" + i, "NotSet"), true);
+				ScaleType st = (ScaleType)Enum.Parse(typeof(ScaleType), FetchString(dict, $"scale_type{i}", "NotSet"), true);
 				if (st != ScaleType.NotSet)
 					sp.ScaleTypeX = sp.ScaleTypeY = st;
 
 				//scaleN controls both scaling type in horizontal and vertical directions. If scaleN is defined, scale_xN and scale_yN have no effect.
-				sp.Scale.X = FetchFloat(dict, "scale_x" + i, 1);
+				sp.Scale.X = FetchFloat(dict, $"scale_x{i}", 1);
-				sp.Scale.Y = FetchFloat(dict, "scale_y" + i, 1);
+				sp.Scale.Y = FetchFloat(dict, $"scale_y{i}", 1);
-				float scale = FetchFloat(dict, "scale" + i, -999);
+				float scale = FetchFloat(dict, $"scale{i}", -999);
 				if (scale != -999)
-					sp.Scale.X = sp.Scale.Y = FetchFloat(dict, "scale" + i, 1);
+					sp.Scale.X = sp.Scale.Y = FetchFloat(dict, $"scale{i}", 1);
 
 				//TODO - LUTs
 			}
@@ -251,7 +251,7 @@ namespace BizHawk.Client.EmuHawk.Filters
 
 		public override string ToString()
 		{
-			return string.Format("RetroShaderPass[#{0}]", RSI);
+			return $"RetroShaderPass[#{RSI}]";
 		}
 
 		public RetroShaderPass(RetroShaderChain RSC, int index)

BizHawk.Client.EmuHawk/Extensions/ToolExtensions.cs

@@ -105,8 +105,8 @@ namespace BizHawk.Client.EmuHawk.ToolExtensions
 
 							//make a menuitem to let you explore to it
 							var tsmiExplore = new ToolStripMenuItem { Text = "&Explore" };
-							string explorePath = "\"" + hf.FullPathWithoutMember + "\"";
+							string explorePath = $"\"{hf.FullPathWithoutMember}\"";
-							tsmiExplore.Click += (o, ev) => { System.Diagnostics.Process.Start("explorer.exe", "/select, " + explorePath); };
+							tsmiExplore.Click += (o, ev) => { System.Diagnostics.Process.Start("explorer.exe", $"/select, {explorePath}"); };
 							tsdd.Items.Add(tsmiExplore);
 
 							var tsmiCopyFile = new ToolStripMenuItem { Text = "Copy &File" };
@@ -217,12 +217,12 @@ namespace BizHawk.Client.EmuHawk.ToolExtensions
 			GlobalWin.Sound.StopSound();
 			if (recent.Frozen)
 			{
-				var result = MessageBox.Show("Could not open " + path, "File not found", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				var result = MessageBox.Show($"Could not open {path}", "File not found", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 			else
 			{
 				// ensure topmost, not to have to minimize everything to see and use our modal window, if it somehow got covered
-				var result = MessageBox.Show(new Form(){TopMost = true},"Could not open " + path + "\nRemove from list?", "File not found", MessageBoxButtons.YesNo, MessageBoxIcon.Error);
+				var result = MessageBox.Show(new Form(){TopMost = true}, $"Could not open {path}\nRemove from list?", "File not found", MessageBoxButtons.YesNo, MessageBoxIcon.Error);
 				if (result == DialogResult.Yes)
 				{
 					if (encodedPath != null)

BizHawk.Client.EmuHawk/Input/GamePad.cs

@@ -220,19 +220,19 @@ namespace BizHawk.Client.EmuHawk
 			for (int i = 0; i < state.GetButtons().Length; i++)
 			{
 				int j = i;
-				AddItem(string.Format("B{0}", i + 1), () => state.IsPressed(j));
+				AddItem($"B{i + 1}", () => state.IsPressed(j));
 			}
 
 			for (int i = 0; i < state.GetPointOfViewControllers().Length; i++)
 			{
 				int j = i;
-				AddItem(string.Format("POV{0}U", i + 1),
+				AddItem($"POV{i + 1}U",
 					() => { int t = state.GetPointOfViewControllers()[j]; return (t >= 0 && t <= 4500) || (t >= 31500 && t < 36000); });
-				AddItem(string.Format("POV{0}D", i + 1),
+				AddItem($"POV{i + 1}D",
 					() => { int t = state.GetPointOfViewControllers()[j]; return t >= 13500 && t <= 22500; });
-				AddItem(string.Format("POV{0}L", i + 1),
+				AddItem($"POV{i + 1}L",
 					() => { int t = state.GetPointOfViewControllers()[j]; return t >= 22500 && t <= 31500; });
-				AddItem(string.Format("POV{0}R", i + 1),
+				AddItem($"POV{i + 1}R",
 					() => { int t = state.GetPointOfViewControllers()[j]; return t >= 4500 && t <= 13500; });
 			}
 		}

BizHawk.Client.EmuHawk/Input/IPCKeyInput.cs

@@ -25,7 +25,7 @@ namespace BizHawk.Client.EmuHawk
 
 		static void IPCThread()
 		{
-			string pipeName = string.Format("bizhawk-pid-{0}-IPCKeyInput", System.Diagnostics.Process.GetCurrentProcess().Id);
+			string pipeName = $"bizhawk-pid-{System.Diagnostics.Process.GetCurrentProcess().Id}-IPCKeyInput";
 
 
 			for (; ; )

BizHawk.Client.EmuHawk/Input/Input.cs

@@ -198,7 +198,7 @@ namespace BizHawk.Client.EmuHawk
 			public InputEventType EventType;
 			public override string ToString()
 			{
-				return string.Format("{0}:{1}", EventType.ToString(), LogicalButton.ToString());
+				return $"{EventType.ToString()}:{LogicalButton.ToString()}";
 			}
 		}
 
@@ -360,7 +360,7 @@ namespace BizHawk.Client.EmuHawk
 						//analyze xinput
 						foreach (var pad in GamePad360.EnumerateDevices())
 						{
-							string xname = "X" + pad.PlayerNumber + " ";
+							string xname = $"X{pad.PlayerNumber} ";
 							for (int b = 0; b < pad.NumButtons; b++)
 								HandleButton(xname + pad.ButtonName(b), pad.Pressed(b));
 							foreach (var sv in pad.GetFloats())
@@ -376,7 +376,7 @@ namespace BizHawk.Client.EmuHawk
 						//analyze joysticks
 						foreach (var pad in GamePad.EnumerateDevices())
 						{
-							string jname = "J" + pad.PlayerNumber + " ";
+							string jname = $"J{pad.PlayerNumber} ";
 							for (int b = 0; b < pad.NumButtons; b++)
 								HandleButton(jname + pad.ButtonName(b), pad.Pressed(b));
 							foreach (var sv in pad.GetFloats())
@@ -513,7 +513,7 @@ namespace BizHawk.Client.EmuHawk
 					foreach (var kvp in LastState)
 						if (kvp.Value)
 						{
-							Console.WriteLine("Unpressing " + kvp.Key);
+							Console.WriteLine($"Unpressing {kvp.Key}");
 							UnpressState[kvp.Key] = true;
 						}
 

BizHawk.Client.EmuHawk/Input/OTK_Gamepad.cs

@@ -23,7 +23,7 @@ namespace BizHawk.Client.EmuHawk
 				JoystickState jss = Joystick.GetState(i);
 				if (jss.IsConnected)
 				{
-					Console.WriteLine(string.Format("joydevice index: {0}", i)); //OpenTK doesn't expose the GUID, even though it stores it internally...
+					Console.WriteLine($"joydevice index: {i}"); //OpenTK doesn't expose the GUID, even though it stores it internally...
 
 					OTK_GamePad ogp = new OTK_GamePad(i);
 					Devices.Add(ogp);
@@ -77,7 +77,7 @@ namespace BizHawk.Client.EmuHawk
 			return state;
 		}
 
-		public string Name { get { return "Joystick " + _stickIdx; } }
+		public string Name { get { return $"Joystick {_stickIdx}"; } }
 		public Guid Guid { get { return _guid; } }
 
 
@@ -122,17 +122,17 @@ namespace BizHawk.Client.EmuHawk
 			int jb = 1;
 			for (int i = 0; i < 64; i++)
 			{
-				AddItem(string.Format("B{0}", jb), () => state.GetButton(i)==ButtonState.Pressed);
+				AddItem($"B{jb}", () => state.GetButton(i)==ButtonState.Pressed);
 				jb++;
 			}
 
 			jb = 1;
 			foreach (JoystickHat enval in Enum.GetValues(typeof(JoystickHat)))
 			{
-				AddItem(string.Format("POV{0}U", jb), () => state.GetHat(enval).IsUp);
+				AddItem($"POV{jb}U", () => state.GetHat(enval).IsUp);
-				AddItem(string.Format("POV{0}D", jb), () => state.GetHat(enval).IsDown);
+				AddItem($"POV{jb}D", () => state.GetHat(enval).IsDown);
-				AddItem(string.Format("POV{0}L", jb), () => state.GetHat(enval).IsLeft);
+				AddItem($"POV{jb}L", () => state.GetHat(enval).IsLeft);
-				AddItem(string.Format("POV{0}R", jb), () => state.GetHat(enval).IsRight);
+				AddItem($"POV{jb}R", () => state.GetHat(enval).IsRight);
 				jb++;
 			}
 		}

BizHawk.Client.EmuHawk/JumpLists.cs

@@ -49,7 +49,7 @@ namespace BizHawk.Client.EmuHawk
 				dynamic ji = Activator.CreateInstance(JumpTask);
 
 				ji.ApplicationPath = exepath;
-				ji.Arguments = '"' + fullpath + '"';
+				ji.Arguments = $"\"{fullpath}\"";
 				ji.Title = title;
 				// for some reason, this doesn't work
 				ji.WorkingDirectory = Path.GetDirectoryName(exepath);

BizHawk.Client.EmuHawk/LogConsole.cs

@@ -118,7 +118,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			string remainder = cmdLine.Substring(childCmdLine);
 			string path = cmdLine.Substring(lastSlash, lastGood - lastSlash);
-			return path + " " + remainder;
+			return $"{path} {remainder}";
 		}
 
 		static IntPtr oldOut, conOut;
@@ -164,7 +164,7 @@ namespace BizHawk.Client.EmuHawk
 					hasConsole = true;
 				}
 				else
-					System.Windows.Forms.MessageBox.Show(string.Format("Couldn't allocate win32 console: {0}", Marshal.GetLastWin32Error()));
+					System.Windows.Forms.MessageBox.Show($"Couldn't allocate win32 console: {Marshal.GetLastWin32Error()}");
 			}
 
 			if(hasConsole)

BizHawk.Client.EmuHawk/MainForm.Events.cs

@@ -443,12 +443,12 @@ namespace BizHawk.Client.EmuHawk
 
 		private void SaveToCurrentSlotMenuItem_Click(object sender, EventArgs e)
 		{
-			SaveQuickSave("QuickSave" + Global.Config.SaveSlot);
+			SaveQuickSave($"QuickSave{Global.Config.SaveSlot}");
 		}
 
 		private void LoadCurrentSlotMenuItem_Click(object sender, EventArgs e)
 		{
-			LoadQuickSave("QuickSave" + Global.Config.SaveSlot);
+			LoadQuickSave($"QuickSave{Global.Config.SaveSlot}");
 		}
 
 		private void FlushSaveRAMMenuItem_Click(object sender, EventArgs e)
@@ -683,7 +683,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void ScreenshotAsMenuItem_Click(object sender, EventArgs e)
 		{
-			var path = string.Format(PathManager.ScreenshotPrefix(Global.Game) + ".{0:yyyy-MM-dd HH.mm.ss}.png", DateTime.Now);
+			var path = $"{PathManager.ScreenshotPrefix(Global.Game)}.{DateTime.Now:yyyy-MM-dd HH.mm.ss}.png";
 
 			var sfd = new SaveFileDialog
 			{
@@ -1364,7 +1364,7 @@ namespace BizHawk.Client.EmuHawk
 			Global.Config = ConfigService.Load<Config>(PathManager.DefaultIniPath);
 			Global.Config.ResolveDefaults();
 			InitControls(); // rebind hotkeys
-			GlobalWin.OSD.AddMessage("Config file loaded: " + PathManager.DefaultIniPath);
+			GlobalWin.OSD.AddMessage($"Config file loaded: {PathManager.DefaultIniPath}");
 		}
 
 		private void LoadConfigFromMenuItem_Click(object sender, EventArgs e)
@@ -1383,7 +1383,7 @@ namespace BizHawk.Client.EmuHawk
 				Global.Config = ConfigService.Load<Config>(ofd.FileName);
 				Global.Config.ResolveDefaults();
 				InitControls(); // rebind hotkeys
-				GlobalWin.OSD.AddMessage("Config file loaded: " + ofd.FileName);
+				GlobalWin.OSD.AddMessage($"Config file loaded: {ofd.FileName}");
 			}
 		}
 
@@ -1601,10 +1601,10 @@ namespace BizHawk.Client.EmuHawk
 
 			for (int i = 0; i < 16; i++)
 			{
-				var str = "FDS Insert " + i;
+				var str = $"FDS Insert {i}";
 				if (Emulator.ControllerDefinition.BoolButtons.Contains(str))
 				{
-					FdsInsertDiskMenuAdd("Insert Disk " + i, str, "FDS Disk " + i + " inserted.");
+					FdsInsertDiskMenuAdd($"Insert Disk {i}", str, $"FDS Disk {i} inserted.");
 				}
 			}
 		}
@@ -2440,8 +2440,8 @@ namespace BizHawk.Client.EmuHawk
 				{
 					var menuItem = new ToolStripMenuItem
 					{
-						Name = "Disk" + (i + 1),
+						Name = $"Disk{i + 1}",
-						Text = "Disk" + (i + 1),
+						Text = $"Disk{i + 1}",
 						Checked = appleII.CurrentDisk == i
 					};
 
@@ -2479,8 +2479,8 @@ namespace BizHawk.Client.EmuHawk
 				{
 					var menuItem = new ToolStripMenuItem
 					{
-						Name = "Disk" + (i + 1),
+						Name = $"Disk{i + 1}",
-						Text = "Disk" + (i + 1),
+						Text = $"Disk{i + 1}",
 						Checked = c64.CurrentDisk == i
 					};
 
@@ -2581,8 +2581,8 @@ namespace BizHawk.Client.EmuHawk
 
                     var menuItem = new ToolStripMenuItem
                     {
-                        Name = i + "_" + name,
+                        Name = $"{i}_{name}",
-                        Text = i + ": " + name,
+                        Text = $"{i}: {name}",
                         Checked = currSel == i
                     };
 
@@ -2616,8 +2616,8 @@ namespace BizHawk.Client.EmuHawk
 
                     var menuItem = new ToolStripMenuItem
                     {
-                        Name = i + "_" + name,
+                        Name = $"{i}_{name}",
-                        Text = i + ": " + name,
+                        Text = $"{i}: {name}",
                         Checked = currSel == i
                     };
 
@@ -2705,8 +2705,8 @@ namespace BizHawk.Client.EmuHawk
 
                     var menuItem = new ToolStripMenuItem
                     {
-                        Name = i + "_" + name,
+                        Name = $"{i}_{name}",
-                        Text = i + ": " + name,
+                        Text = $"{i}: {name}",
                         Checked = currSel == i
                     };
 
@@ -2740,8 +2740,8 @@ namespace BizHawk.Client.EmuHawk
 
                     var menuItem = new ToolStripMenuItem
                     {
-                        Name = i + "_" + name,
+                        Name = $"{i}_{name}",
-                        Text = i + ": " + name,
+                        Text = $"{i}: {name}",
                         Checked = currSel == i
                     };
 
@@ -2879,23 +2879,19 @@ namespace BizHawk.Client.EmuHawk
 				}
 			}
 
-			var file = new FileInfo(
+			var file = new FileInfo($"{PathManager.SaveStatePrefix(Global.Game)}.QuickSave{Global.Config.SaveSlot}.State.bak");
-				PathManager.SaveStatePrefix(Global.Game) +
-				".QuickSave" +
-				Global.Config.SaveSlot +
-				".State.bak");
 
 			if (file.Exists)
 			{
 				UndoSavestateContextMenuItem.Enabled = true;
 				if (_stateSlots.IsRedo(Global.Config.SaveSlot))
 				{
-					UndoSavestateContextMenuItem.Text = "Redo Save to slot " + Global.Config.SaveSlot;
+					UndoSavestateContextMenuItem.Text = $"Redo Save to slot {Global.Config.SaveSlot}";
 					UndoSavestateContextMenuItem.Image = Properties.Resources.redo;
 				}
 				else
 				{
-					UndoSavestateContextMenuItem.Text = "Undo Save to slot " + Global.Config.SaveSlot;
+					UndoSavestateContextMenuItem.Text = $"Undo Save to slot {Global.Config.SaveSlot}";
 					UndoSavestateContextMenuItem.Image = Properties.Resources.undo;
 				}
 			}
@@ -3025,13 +3021,9 @@ namespace BizHawk.Client.EmuHawk
 
 		private void UndoSavestateContextMenuItem_Click(object sender, EventArgs e)
 		{
-			_stateSlots.SwapBackupSavestate(
+			_stateSlots.SwapBackupSavestate($"{PathManager.SaveStatePrefix(Global.Game)}.QuickSave{Global.Config.SaveSlot}.State");
-				PathManager.SaveStatePrefix(Global.Game) +
-				".QuickSave" +
-				Global.Config.SaveSlot +
-				".State");
 
-			GlobalWin.OSD.AddMessage("Save slot " + Global.Config.SaveSlot + " restored.");
+			GlobalWin.OSD.AddMessage($"Save slot {Global.Config.SaveSlot} restored.");
 		}
 
 		private void ClearSramContextMenuItem_Click(object sender, EventArgs e)
@@ -3078,12 +3070,12 @@ namespace BizHawk.Client.EmuHawk
 			{
 				if (_stateSlots.HasSlot(slot))
 				{
-					LoadQuickSave("QuickSave" + slot);
+					LoadQuickSave($"QuickSave{slot}");
 				}
 			}
 			else if (e.Button == MouseButtons.Right)
 			{
-				SaveQuickSave("QuickSave" + slot);
+				SaveQuickSave($"QuickSave{slot}");
 			}
 		}
 
@@ -3138,7 +3130,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			GlobalWin.Sound.StopSound();
 			DialogResult result = MessageBox.Show(this,
-				"Version " + Global.Config.Update_LatestVersion + " is now available. Would you like to open the BizHawk homepage?\r\n\r\nClick \"No\" to hide the update notification for this version.",
+				$"Version {Global.Config.Update_LatestVersion} is now available. Would you like to open the BizHawk homepage?\r\n\r\nClick \"No\" to hide the update notification for this version.",
 				"New Version Available", MessageBoxButtons.YesNoCancel, MessageBoxIcon.Question);
 			GlobalWin.Sound.StartSound();
 
@@ -3273,7 +3265,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch (Exception ex)
 			{
-				MessageBox.Show("Exception on drag and drop:\n" + ex);
+				MessageBox.Show($"Exception on drag and drop:\n{ex}");
 			}
 		}
 

BizHawk.Client.EmuHawk/MainForm.Hotkey.cs

@@ -30,10 +30,10 @@ namespace BizHawk.Client.EmuHawk
 					HardReset();
 					break;
 				case "Quick Load": 
-					LoadQuickSave("QuickSave" + Global.Config.SaveSlot); 
+					LoadQuickSave($"QuickSave{Global.Config.SaveSlot}");
 					break;
 				case "Quick Save": 
-					SaveQuickSave("QuickSave" + Global.Config.SaveSlot);
+					SaveQuickSave($"QuickSave{Global.Config.SaveSlot}");
 					break;
 				case "Clear Autohold":
 					ClearAutohold();
@@ -126,7 +126,7 @@ namespace BizHawk.Client.EmuHawk
 					break;
 				case "Toggle Skip Lag Frame":
 					Global.Config.SkipLagFrame ^= true;
-					GlobalWin.OSD.AddMessage("Skip Lag Frames toggled " + (Global.Config.SkipLagFrame ? "On" : "Off"));
+					GlobalWin.OSD.AddMessage($"Skip Lag Frames toggled {(Global.Config.SkipLagFrame ? "On" : "Off")}");
 					break;
 				case "Toggle Key Priority":
 					ToggleKeyPriority();
@@ -348,7 +348,7 @@ namespace BizHawk.Client.EmuHawk
 						}
 
 						Global.CheatList.ToList().ForEach(x => x.Toggle());
-						GlobalWin.OSD.AddMessage("Cheats toggled" + type);
+						GlobalWin.OSD.AddMessage($"Cheats toggled{type}");
 					}
 
 					break;
@@ -642,7 +642,7 @@ namespace BizHawk.Client.EmuHawk
 						var s = ((Gameboy)Emulator).GetSettings();
 						s.DisplayBG ^= true;
 						((Gameboy)Emulator).PutSettings(s);
-						GlobalWin.OSD.AddMessage("BG toggled " + (s.DisplayBG ? "on" : "off"));
+						GlobalWin.OSD.AddMessage($"BG toggled {(s.DisplayBG ? "on" : "off")}");
 					}
 
 					break;
@@ -652,7 +652,7 @@ namespace BizHawk.Client.EmuHawk
 						var s = ((Gameboy)Emulator).GetSettings();
 						s.DisplayOBJ ^= true;
 						((Gameboy)Emulator).PutSettings(s);
-						GlobalWin.OSD.AddMessage("OBJ toggled " + (s.DisplayBG ? "on" : "off"));
+						GlobalWin.OSD.AddMessage($"OBJ toggled {(s.DisplayBG ? "on" : "off")}");
 					}
 
 					break;

BizHawk.Client.EmuHawk/MainForm.cs

@@ -279,7 +279,7 @@ namespace BizHawk.Client.EmuHawk
 				LoadRom(argParser.cmdRom, new LoadRomArgs { OpenAdvanced = ioa });
 				if (Global.Game == null)
 				{
-					MessageBox.Show("Failed to load " + argParser.cmdRom + " specified on commandline");
+					MessageBox.Show($"Failed to load {argParser.cmdRom} specified on commandline");
 				}
 			}
 			else if (Global.Config.RecentRoms.AutoLoad && !Global.Config.RecentRoms.Empty)
@@ -370,11 +370,11 @@ namespace BizHawk.Client.EmuHawk
 				}
 				else if (argParser.cmdLoadSlot != null)
 				{
-					LoadQuickSave("QuickSave" + argParser.cmdLoadSlot);
+					LoadQuickSave($"QuickSave{argParser.cmdLoadSlot}");
 				}
 				else if (Global.Config.AutoLoadLastSaveSlot)
 				{
-					LoadQuickSave("QuickSave" + Global.Config.SaveSlot);
+					LoadQuickSave($"QuickSave{Global.Config.SaveSlot}");
 				}
 			}
 
@@ -918,34 +918,22 @@ namespace BizHawk.Client.EmuHawk
 
 		public void TakeScreenshot()
 		{
-			string fmt = "{0}.{1:yyyy-MM-dd HH.mm.ss}{2}.png";
+			var basename = $"{PathManager.ScreenshotPrefix(Global.Game)}.{DateTime.Now:yyyy-MM-dd HH.mm.ss}";
-			string prefix = PathManager.ScreenshotPrefix(Global.Game);
-			var ts = DateTime.Now;
 
-			string fnameBare = string.Format(fmt, prefix, ts, "");
+			var fnameBare = $"{basename}.png";
-			string fname = string.Format(fmt, prefix, ts, " (0)");
+			var fname = $"{basename} (0).png";
 
 			// if the (0) filename exists, do nothing. we'll bump up the number later
 			// if the bare filename exists, move it to (0)
 			// otherwise, no related filename exists, and we can proceed with the bare filename
-			if (File.Exists(fname))
+			if (!File.Exists(fname))
 			{
-			}
+				if (File.Exists(fnameBare)) File.Move(fnameBare, fname);
-			else if (File.Exists(fnameBare))
+				else fname = fnameBare;
-			{
-				File.Move(fnameBare, fname);
-			}
-			else
-			{
-				fname = fnameBare;
 			}
 
-			int seq = 0;
+			for (var seq = 0; File.Exists(fname); seq++)
-			while (File.Exists(fname))
+				fname = $"{basename} ({seq}).png";
-			{
-				var sequence = $" ({seq++})";
-				fname = string.Format(fmt, prefix, ts, sequence);
-			}
 
 			TakeScreenshot(fname);
 		}
@@ -967,10 +955,10 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			/*
-			using (var fs = new FileStream(path + "_test.bmp", FileMode.OpenOrCreate, FileAccess.Write))
+			using (var fs = new FileStream($"{path}_test.bmp", FileMode.OpenOrCreate, FileAccess.Write))
 				QuickBmpFile.Save(Emulator.VideoProvider(), fs, r.Next(50, 500), r.Next(50, 500));
 			*/
-			GlobalWin.OSD.AddMessage(fi.Name + " saved.");
+			GlobalWin.OSD.AddMessage($"{fi.Name} saved.");
 		}
 
 		public void FrameBufferResized()
@@ -996,7 +984,7 @@ namespace BizHawk.Client.EmuHawk
 					}
 				}
 
-				Console.WriteLine("Selecting display size " + lastComputedSize);
+				Console.WriteLine($"Selecting display size {lastComputedSize}");
 
 				// Change size
 				Size = new Size(lastComputedSize.Width + borderWidth, lastComputedSize.Height + borderHeight);
@@ -1176,7 +1164,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public void FrameSkipMessage()
 		{
-			GlobalWin.OSD.AddMessage("Frameskipping set to " + Global.Config.FrameSkip);
+			GlobalWin.OSD.AddMessage($"Frameskipping set to {Global.Config.FrameSkip}");
 		}
 
 		public void UpdateCheatStatus()
@@ -1253,7 +1241,7 @@ namespace BizHawk.Client.EmuHawk
 				((Snes9x)Emulator).PutSettings(s);
 			}
 
-			GlobalWin.OSD.AddMessage($"BG {layer} Layer " + (result ? "On" : "Off"));
+			GlobalWin.OSD.AddMessage($"BG {layer} Layer {(result ? "On" : "Off")}");
 		}
 
 		private void SNES_ToggleObj(int layer)
@@ -1289,7 +1277,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 
 				((LibsnesCore)Emulator).PutSettings(s);
-				GlobalWin.OSD.AddMessage($"Obj {layer} Layer " + (result ? "On" : "Off"));
+				GlobalWin.OSD.AddMessage($"Obj {layer} Layer {(result ? "On" : "Off")}");
 			}
 			else if (Emulator is Snes9x)
 			{
@@ -1311,7 +1299,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 
 				((Snes9x)Emulator).PutSettings(s);
-				GlobalWin.OSD.AddMessage($"Sprite {layer} Layer " + (result ? "On" : "Off"));
+				GlobalWin.OSD.AddMessage($"Sprite {layer} Layer {(result ? "On" : "Off")}");
 			}
 		}
 
@@ -1448,7 +1436,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (!string.IsNullOrEmpty(VersionInfo.CustomBuildString))
 			{
-				str += VersionInfo.CustomBuildString + " ";
+				str += $"{VersionInfo.CustomBuildString} ";
 			}
 
 			str += Emulator.IsNull() ? "BizHawk" : Global.SystemInfo.DisplayName;
@@ -1460,11 +1448,11 @@ namespace BizHawk.Client.EmuHawk
 
 			if (!Emulator.IsNull())
 			{
-				str += " - " + Global.Game.Name;
+				str += $" - {Global.Game.Name}";
 
 				if (Global.MovieSession.Movie.IsActive)
 				{
-					str += " - " + Path.GetFileName(Global.MovieSession.Movie.Filename);
+					str += $" - {Path.GetFileName(Global.MovieSession.Movie.Filename)}";
 				}
 			}
 
@@ -1635,9 +1623,9 @@ namespace BizHawk.Client.EmuHawk
 					path = PathManager.SaveRamPath(Global.Game);
 				}
 				var file = new FileInfo(path);
-				var newPath = path + ".new";
+				var newPath = $"{path}.new";
 				var newFile = new FileInfo(newPath);
-				var backupPath = path + ".bak";
+				var backupPath = $"{path}.bak";
 				var backupFile = new FileInfo(backupPath);
 				if (file.Directory != null && !file.Directory.Exists)
 				{
@@ -1647,7 +1635,7 @@ namespace BizHawk.Client.EmuHawk
                     }
                     catch
                     {
-                        GlobalWin.OSD.AddMessage("Unable to flush SaveRAM to: " + newFile.Directory);                        
+                        GlobalWin.OSD.AddMessage($"Unable to flush SaveRAM to: {newFile.Directory}");
                         return false;
                     }
 				}
@@ -1909,13 +1897,13 @@ namespace BizHawk.Client.EmuHawk
 			{
 				PauseStatusButton.Image = Properties.Resources.Lightning;
 				PauseStatusButton.Visible = true;
-				PauseStatusButton.ToolTipText = "Emulator is turbo seeking to frame " + PauseOnFrame.Value + " click to stop seek";
+				PauseStatusButton.ToolTipText = $"Emulator is turbo seeking to frame {PauseOnFrame.Value} click to stop seek";
 			}
 			else if (PauseOnFrame.HasValue)
 			{
 				PauseStatusButton.Image = Properties.Resources.YellowRight;
 				PauseStatusButton.Visible = true;
-				PauseStatusButton.ToolTipText = "Emulator is playing to frame " + PauseOnFrame.Value + " click to stop seek";
+				PauseStatusButton.ToolTipText = $"Emulator is playing to frame {PauseOnFrame.Value} click to stop seek";
 			}
 			else if (EmulatorPaused)
 			{
@@ -1967,14 +1955,14 @@ namespace BizHawk.Client.EmuHawk
 		{
 			Global.Config.SpeedPercentAlternate = value;
 			SyncThrottle();
-			GlobalWin.OSD.AddMessage("Alternate Speed: " + value + "%");
+			GlobalWin.OSD.AddMessage($"Alternate Speed: {value}%");
 		}
 
 		private void SetSpeedPercent(int value)
 		{
 			Global.Config.SpeedPercent = value;
 			SyncThrottle();
-			GlobalWin.OSD.AddMessage("Speed: " + value + "%");
+			GlobalWin.OSD.AddMessage($"Speed: {value}%");
 		}
 
 		private void Shutdown()
@@ -2328,7 +2316,7 @@ namespace BizHawk.Client.EmuHawk
 				Global.Config.SoundVolume = 100;
 			}
 
-			GlobalWin.OSD.AddMessage("Volume " + Global.Config.SoundVolume);
+			GlobalWin.OSD.AddMessage($"Volume {Global.Config.SoundVolume}");
 		}
 
 		private static void VolumeDown()
@@ -2339,7 +2327,7 @@ namespace BizHawk.Client.EmuHawk
 				Global.Config.SoundVolume = 0;
 			}
 
-			GlobalWin.OSD.AddMessage("Volume " + Global.Config.SoundVolume);
+			GlobalWin.OSD.AddMessage($"Volume {Global.Config.SoundVolume}");
 		}
 
 		private void SoftReset()
@@ -2438,7 +2426,7 @@ namespace BizHawk.Client.EmuHawk
 					return;
 			}
 
-			GlobalWin.OSD.AddMessage("Screensize set to " + Global.Config.TargetZoomFactors[Emulator.SystemId] + "x");
+			GlobalWin.OSD.AddMessage($"Screensize set to {Global.Config.TargetZoomFactors[Emulator.SystemId]}x");
 			FrameBufferResized();
 		}
 
@@ -2465,7 +2453,7 @@ namespace BizHawk.Client.EmuHawk
 					return;
 			}
 
-			GlobalWin.OSD.AddMessage("Screensize set to " + Global.Config.TargetZoomFactors[Emulator.SystemId] + "x");
+			GlobalWin.OSD.AddMessage($"Screensize set to {Global.Config.TargetZoomFactors[Emulator.SystemId]}x");
 			FrameBufferResized();
 		}
 
@@ -2624,7 +2612,7 @@ namespace BizHawk.Client.EmuHawk
 			if (Global.MovieSession.Movie.IsActive)
 			{
 				Global.MovieSession.Movie.Save();
-				GlobalWin.OSD.AddMessage(Global.MovieSession.Movie.Filename + " saved.");
+				GlobalWin.OSD.AddMessage($"{Global.MovieSession.Movie.Filename} saved.");
 			}
 		}
 
@@ -2664,9 +2652,7 @@ namespace BizHawk.Client.EmuHawk
 						? _linkCableOn
 						: _linkCableOff;
 
-					LinkConnectStatusBarButton.ToolTipText = Emulator.AsLinkable().LinkConnected
+					LinkConnectStatusBarButton.ToolTipText = $"Link connection is currently {(Emulator.AsLinkable().LinkConnected ? "enabled" : "disabled")}";
-						? "Link connection is currently enabled"
-						: "Link connection is currently disabled";
 				}
 				else
 				{
@@ -2701,21 +2687,18 @@ namespace BizHawk.Client.EmuHawk
 		private static void ToggleModePokeMode()
 		{
 			Global.Config.MoviePlaybackPokeMode ^= true;
-			GlobalWin.OSD.AddMessage(Global.Config.MoviePlaybackPokeMode ? "Movie Poke mode enabled" : "Movie Poke mode disabled");
+			GlobalWin.OSD.AddMessage($"Movie Poke mode {(Global.Config.MoviePlaybackPokeMode ? "enabled" : "disabled")}");
 		}
 
 		private static void ToggleBackgroundInput()
 		{
 			Global.Config.AcceptBackgroundInput ^= true;
-			GlobalWin.OSD.AddMessage(Global.Config.AcceptBackgroundInput
+			GlobalWin.OSD.AddMessage($"Background Input {(Global.Config.AcceptBackgroundInput ? "enabled" : "disabled")}");
-										 ? "Background Input enabled"
-										 : "Background Input disabled");
 		}
 
 		private static void VsyncMessage()
 		{
-			GlobalWin.OSD.AddMessage(
+			GlobalWin.OSD.AddMessage($"Display Vsync set to {(Global.Config.VSync ? "on" : "off")}");
-				"Display Vsync set to " + (Global.Config.VSync ? "on" : "off"));
 		}
 
 		private static bool StateErrorAskUser(string title, string message)
@@ -3276,7 +3259,7 @@ namespace BizHawk.Client.EmuHawk
 						var sfd = new SaveFileDialog();
 						if (Global.Game != null)
 						{
-							sfd.FileName = PathManager.FilesystemSafeName(Global.Game) + "." + ext; // dont use Path.ChangeExtension, it might wreck game names with dots in them
+							sfd.FileName = $"{PathManager.FilesystemSafeName(Global.Game)}.{ext}"; // dont use Path.ChangeExtension, it might wreck game names with dots in them
 							sfd.InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries.AvPathFragment, null);
 						}
 						else
@@ -3465,7 +3448,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				catch (Exception e)
 				{
-					MessageBox.Show("Video dumping died:\n\n" + e);
+					MessageBox.Show($"Video dumping died:\n\n{e}");
 					AbortAv();
 				}
 
@@ -3531,7 +3514,7 @@ namespace BizHawk.Client.EmuHawk
 				string title = "load error";
 				if (e.AttemptedCoreLoad != null)
 				{
-					title = e.AttemptedCoreLoad + " load error";
+					title = $"{e.AttemptedCoreLoad} load error";
 				}
 
 				MessageBox.Show(this, e.Message, title, MessageBoxButtons.OK, MessageBoxIcon.Error);
@@ -3682,7 +3665,7 @@ namespace BizHawk.Client.EmuHawk
 				if (result)
 				{
 
-					string loaderName = "*" + OpenAdvancedSerializer.Serialize(ioa);
+					string loaderName = $"*{OpenAdvancedSerializer.Serialize(ioa)}";
 					Emulator = loader.LoadedEmulator;
 					Global.Game = loader.Game;
 					CoreFileProvider.SyncCoreCommInputSignals(nextComm);
@@ -3714,8 +3697,8 @@ namespace BizHawk.Client.EmuHawk
 								else
 								{
 									xSw.WriteLine(xmlGame.Assets[xg].Key);
-									xSw.WriteLine("SHA1:" + xmlGame.Assets[xg].Value.HashSHA1());
+									xSw.WriteLine($"SHA1:{xmlGame.Assets[xg].Value.HashSHA1()}");
-									xSw.WriteLine("MD5:" + xmlGame.Assets[xg].Value.HashMD5());
+									xSw.WriteLine($"MD5:{xmlGame.Assets[xg].Value.HashMD5()}");
 									xSw.WriteLine();
 								}
 							}
@@ -3829,7 +3812,7 @@ namespace BizHawk.Client.EmuHawk
 					ToolFormBase.UpdateCheatRelatedTools(null, null);
 					if (Global.Config.AutoLoadLastSaveSlot && _stateSlots.HasSlot(Global.Config.SaveSlot))
 					{
-						LoadQuickSave("QuickSave" + Global.Config.SaveSlot);
+						LoadQuickSave($"QuickSave{Global.Config.SaveSlot}");
 					}
 
 					if (Global.FirmwareManager.RecentlyServed.Count > 0)
@@ -3971,7 +3954,7 @@ namespace BizHawk.Client.EmuHawk
 				GlobalWin.Tools.Restart();
 				ApiManager.Restart(Emulator.ServiceProvider);
 				RewireSound();
-				Text = "BizHawk" + (VersionInfo.DeveloperBuild ? " (interim) " : "");
+				Text = $"BizHawk{(VersionInfo.DeveloperBuild ? " (interim) " : "")}";
 				HandlePlatformMenus();
 				_stateSlots.Clear();
 				UpdateDumpIcon();
@@ -3999,7 +3982,7 @@ namespace BizHawk.Client.EmuHawk
 		public void EnableRewind(bool enabled)
 		{
 			Global.Rewinder.SuspendRewind = !enabled;
-			GlobalWin.OSD.AddMessage("Rewind " + (enabled ? "enabled" : "suspended"));
+			GlobalWin.OSD.AddMessage($"Rewind {(enabled ? "enabled" : "suspended")}");
 		}
 
 		public void ClearRewindData()
@@ -4079,7 +4062,7 @@ namespace BizHawk.Client.EmuHawk
 
 				if (!supressOSD)
 				{
-					GlobalWin.OSD.AddMessage("Loaded state: " + userFriendlyStateName);
+					GlobalWin.OSD.AddMessage($"Loaded state: {userFriendlyStateName}");
 				}
 			}
 			else
@@ -4110,10 +4093,10 @@ namespace BizHawk.Client.EmuHawk
 				return;
 			}
 
-			var path = PathManager.SaveStatePrefix(Global.Game) + "." + quickSlotName + ".State";
+			var path = $"{PathManager.SaveStatePrefix(Global.Game)}.{quickSlotName}.State";
 			if (!File.Exists(path))
 			{
-				GlobalWin.OSD.AddMessage("Unable to load " + quickSlotName + ".State");
+				GlobalWin.OSD.AddMessage($"Unable to load {quickSlotName}.State");
 
 				return;
 			}
@@ -4140,11 +4123,11 @@ namespace BizHawk.Client.EmuHawk
 
 				ClientApi.OnStateSaved(this, userFriendlyStateName);
 
-				GlobalWin.OSD.AddMessage("Saved state: " + userFriendlyStateName);
+				GlobalWin.OSD.AddMessage($"Saved state: {userFriendlyStateName}");
 			}
 			catch (IOException)
 			{
-				GlobalWin.OSD.AddMessage("Unable to save state " + path);
+				GlobalWin.OSD.AddMessage($"Unable to save state {path}");
 			}
 
 			if (!fromLua)
@@ -4174,7 +4157,7 @@ namespace BizHawk.Client.EmuHawk
 				return;
 			}
 
-			var path = PathManager.SaveStatePrefix(Global.Game) + "." + quickSlotName + ".State";
+			var path = $"{PathManager.SaveStatePrefix(Global.Game)}.{quickSlotName}.State";
 
 			var file = new FileInfo(path);
 			if (file.Directory != null && !file.Directory.Exists)
@@ -4185,7 +4168,7 @@ namespace BizHawk.Client.EmuHawk
 			// Make backup first
 			if (Global.Config.BackupSavestates)
 			{
-				Util.TryMoveBackupFile(path, path + ".bak");
+				Util.TryMoveBackupFile(path, $"{path}.bak");
 			}
 
 			SaveState(path, quickSlotName, false);
@@ -4230,7 +4213,7 @@ namespace BizHawk.Client.EmuHawk
 				DefaultExt = "State",
 				Filter = "Save States (*.State)|*.State|All Files|*.*",
 				InitialDirectory = path,
-				FileName = PathManager.SaveStatePrefix(Global.Game) + "." + "QuickSave0.State"
+				FileName = $"{PathManager.SaveStatePrefix(Global.Game)}.QuickSave0.State"
 			};
 
 			var result = sfd.ShowHawkDialog();

BizHawk.Client.EmuHawk/OpenAdvancedChooser.cs

@@ -103,7 +103,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				if (!bootstrap)
 				{
-					MessageBox.Show("Couldn't load the selected Libretro core for analysis. It won't be available.\n\nError:\n\n" + ex.ToString());
+					MessageBox.Show($"Couldn't load the selected Libretro core for analysis. It won't be available.\n\nError:\n\n{ex}");
 				}
 			}
 		}

BizHawk.Client.EmuHawk/PlatformChooser.cs

@@ -37,11 +37,11 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (RomGame.RomData.Length > 10 * 1024 * 1024) // If 10mb, show in megabytes
 			{
-				RomSizeLabel.Text = string.Format("{0:n0}", (RomGame.RomData.Length / 1024 / 1024)) + "mb";
+				RomSizeLabel.Text = $"{RomGame.RomData.Length / 1024 / 1024:n0}mb";
 			}
 			else
 			{
-				RomSizeLabel.Text = string.Format("{0:n0}", (RomGame.RomData.Length / 1024)) + "kb";
+				RomSizeLabel.Text = $"{RomGame.RomData.Length / 1024:n0}kb";
 			}
 
 			ExtensionLabel.Text = RomGame.Extension.ToLower();

BizHawk.Client.EmuHawk/Program.cs

@@ -125,7 +125,7 @@ namespace BizHawk.Client.EmuHawk
 							{
 								var result = MessageBox.Show(
 									"EmuHawk has thrown a fatal exception and is about to close.\nA movie has been detected. Would you like to try to save?\n(Note: Depending on what caused this error, this may or may not succeed)",
-									"Fatal error: " + e.GetType().Name,
+									$"Fatal error: {e.GetType().Name}",
 									MessageBoxButtons.YesNo,
 									MessageBoxIcon.Exclamation
 									);
@@ -173,7 +173,7 @@ namespace BizHawk.Client.EmuHawk
 						{
 							var result = MessageBox.Show(
 								"EmuHawk has thrown a fatal exception and is about to close.\nA movie has been detected. Would you like to try to save?\n(Note: Depending on what caused this error, this may or may not succeed)",
-								"Fatal error: " + e.GetType().Name,
+								$"Fatal error: {e.GetType().Name}",
 								MessageBoxButtons.YesNo,
 								MessageBoxIcon.Exclamation
 								);
@@ -350,7 +350,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public static void RemoveMOTW(string path)
 		{
-			DeleteFileW(path + ":Zone.Identifier");
+			DeleteFileW($"{path}:Zone.Identifier");
 		}
 
 		static void WhackAllMOTW(string dllDir)
@@ -410,7 +410,7 @@ namespace BizHawk.Client.EmuHawk
 						return asm;
 
 				//load missing assemblies by trying to find them in the dll directory
-				string dllname = new AssemblyName(requested).Name + ".dll";
+				string dllname = $"{new AssemblyName(requested).Name}.dll";
 				string directory = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "dll");
 				string simpleName = new AssemblyName(requested).Name;
 				if (simpleName == "NLua" || simpleName == "KopiLua") directory = Path.Combine(directory, "nlua");

BizHawk.Client.EmuHawk/Sound/Utilities/SoundOutputProvider.cs

@@ -167,7 +167,7 @@ namespace BizHawk.Client.EmuHawk
 			if (extraSampleCount < -maxSamplesDeficit)
 			{
 				int generateSampleCount = -extraSampleCount;
-				if (LogDebug) Console.WriteLine("Generating " + generateSampleCount + " samples");
+				if (LogDebug) Console.WriteLine($"Generating {generateSampleCount} samples");
 				for (int i = 0; i < generateSampleCount * ChannelCount; i++)
 				{
 					_buffer.Enqueue(0);
@@ -177,7 +177,7 @@ namespace BizHawk.Client.EmuHawk
 			else if (extraSampleCount > maxSamplesSurplus)
 			{
 				int discardSampleCount = extraSampleCount;
-				if (LogDebug) Console.WriteLine("Discarding " + discardSampleCount + " samples");
+				if (LogDebug) Console.WriteLine($"Discarding {discardSampleCount} samples");
 				for (int i = 0; i < discardSampleCount * ChannelCount; i++)
 				{
 					_buffer.Dequeue();

BizHawk.Client.EmuHawk/Throttle.cs

@@ -35,7 +35,7 @@ namespace BizHawk.Client.EmuHawk
 			//notably, if we're frame-advancing, we should be paused.
 			if (signal_paused && !signal_continuousFrameAdvancing)
 			{
-				//Console.WriteLine("THE THING: {0} {1}", signal_paused ,signal_continuousFrameAdvancing);
+				//Console.WriteLine($"THE THING: {signal_paused} {signal_continuousFrameAdvancing}");
 				skipNextFrame = false;
 				framesSkipped = 0;
 				framesToSkip = 0;
@@ -198,12 +198,12 @@ namespace BizHawk.Client.EmuHawk
 		int pct = -1;
 		public void SetSpeedPercent(int percent)
 		{
-			//Console.WriteLine("throttle set percent " + percent);
+			//Console.WriteLine($"throttle set percent {percent}");
 			if (pct == percent) return;
 			pct = percent;
 			float fraction = percent / 100.0f;
 			desiredfps = (ulong)(core_desiredfps * fraction);
-			//Console.WriteLine("throttle set desiredfps " + desiredfps);
+			//Console.WriteLine($"throttle set desiredfps {desiredfps}");
 			desiredspf = 65536.0f / desiredfps;
 			AutoFrameSkip_IgnorePreviousDelay();
 		}

BizHawk.Client.EmuHawk/UpdateChecker.cs

@@ -107,8 +107,8 @@ namespace BizHawk.Client.EmuHawk
 
 		private static string GetTextFromTag(string info, string tagName)
 		{
-			string openTag = "[" + tagName + "]";
+			string openTag = $"[{tagName}]";
-			string closeTag = "[/" + tagName + "]";
+			string closeTag = $"[/{tagName}]";
 			int start = info.IndexOf(openTag, StringComparison.OrdinalIgnoreCase);
 			if (start == -1) return null;
 			start += openTag.Length;

BizHawk.Client.EmuHawk/config/ControllerConfig.cs

@@ -126,7 +126,7 @@ namespace BizHawk.Client.EmuHawk
 				int i;
 				for (i = MaxPlayers; i > 0; i--)
 				{
-					if (button.StartsWith("P" + i))
+					if (button.StartsWith($"P{i}"))
 					{
 						break;
 					}
@@ -162,7 +162,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (buckets[i].Count > 0)
 					{
-						string tabname = Global.Emulator.SystemId == "WSWAN" ? i == 1 ? "Normal" : "Rotated" : "Player " + i; // hack
+						string tabname = Global.Emulator.SystemId != "WSWAN" ? $"Player {i}" : i == 1 ? "Normal" : "Rotated"; // hack
 						tt.TabPages.Add(tabname);
 						tt.TabPages[pageidx].Controls.Add(createpanel(settings, buckets[i], tt.Size));
 						pageidx++;
@@ -362,7 +362,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void NewControllerConfig_Load(object sender, EventArgs e)
 		{
-			Text = _theDefinition.Name + " Configuration";
+			Text = $"{_theDefinition.Name} Configuration";
 		}
 
 		private static TabControl GetTabControl(IEnumerable controls)

BizHawk.Client.EmuHawk/config/ControllerConfig/AnalogBindControl.cs

@@ -66,13 +66,13 @@ namespace BizHawk.Client.EmuHawk
 		private void TrackBarSensitivity_ValueChanged(object sender, EventArgs e)
 		{
 			_bind.Mult = trackBarSensitivity.Value / 10.0f;
-			labelSensitivity.Text = $"Sensitivity: {(Bind.Mult * 100)}" + "%";
+			labelSensitivity.Text = $"Sensitivity: {Bind.Mult * 100}%";
 		}
 
 		private void TrackBarDeadzone_ValueChanged(object sender, EventArgs e)
 		{
 			_bind.Deadzone = trackBarDeadzone.Value / 20.0f;
-			labelDeadzone.Text = $"Deadzone: {(Bind.Deadzone * 100)}" + "%";
+			labelDeadzone.Text = $"Deadzone: {Bind.Deadzone * 100}%";
 		}
 
 		private void ButtonFlip_Click(object sender, EventArgs e)

BizHawk.Client.EmuHawk/config/DisplayConfigLite.cs

@@ -270,7 +270,7 @@ namespace BizHawk.Client.EmuHawk
 			Global.Config.TargetScanlineFilterIntensity = tbScanlineIntensity.Value;
 			int scanlines = Global.Config.TargetScanlineFilterIntensity;
 			float percentage = (float) scanlines / 256 * 100;
-			lblScanlines.Text = String.Format("{0:F2}", percentage) + "%";
+			lblScanlines.Text = $"{percentage:F2}%";
 		}
 
 		private void trackbarFrameSizeWindowed_ValueChanged(object sender, EventArgs e)

BizHawk.Client.EmuHawk/config/FirmwaresConfig.cs

@@ -109,7 +109,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				else
 				{
-					tbbCloseReload.ToolTipText = "Close Firmware Manager and reload " + reloadRomPath;
+					tbbCloseReload.ToolTipText = $"Close Firmware Manager and reload {reloadRomPath}";
 				}
 
 			}
@@ -313,7 +313,7 @@ namespace BizHawk.Client.EmuHawk
 
 					lvi.SubItems[6].Text = ri.Size.ToString();
 
-					if (ri.Hash != null) lvi.SubItems[7].Text = "sha1:" + ri.Hash;
+					if (ri.Hash != null) lvi.SubItems[7].Text = $"sha1:{ri.Hash}";
 					else lvi.SubItems[7].Text = "";
 				}
 			}
@@ -443,7 +443,7 @@ namespace BizHawk.Client.EmuHawk
                                             }
                                             catch (Exception ex)
                                             {
-                                                MessageBox.Show(this, "There was an issue copying the file. The customization has NOT been set.\n\n" + ex.StackTrace);
+                                                MessageBox.Show(this, $"There was an issue copying the file. The customization has NOT been set.\n\n{ex.StackTrace}");
                                                 continue;
                                             }
                                         }
@@ -456,7 +456,7 @@ namespace BizHawk.Client.EmuHawk
                     }
                     catch (Exception ex)
                     {
-                        MessageBox.Show(this, "There was an issue during the process. The customization has NOT been set.\n\n" + ex.StackTrace);
+                        MessageBox.Show(this, $"There was an issue during the process. The customization has NOT been set.\n\n{ex.StackTrace}");
                         return;
                     }
 
@@ -526,7 +526,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				olvi.SubItems[0].Text = ff.Size.ToString();
 				olvi.SubItems[0].Font = this.Font; // why doesnt this work?
-				olvi.SubItems[1].Text = "sha1:" + o.Hash;
+				olvi.SubItems[1].Text = $"sha1:{o.Hash}";
 				olvi.SubItems[1].Font = fixedFont;
 				olvi.SubItems[2].Text = ff.RecommendedName;
 				olvi.SubItems[2].Font = this.Font; // why doesnt this work?
@@ -648,7 +648,7 @@ namespace BizHawk.Client.EmuHawk
 					if (hf.IsArchive)
 					{
 						// blech. the worst extraction code in the universe.
-						string extractpath = Path.GetTempFileName() + ".dir";
+						string extractpath = $"{Path.GetTempFileName()}.dir";
 						DirectoryInfo di = Directory.CreateDirectory(extractpath);
 
 						try

BizHawk.Client.EmuHawk/config/GB/BmpView.cs

@@ -103,7 +103,7 @@ namespace BizHawk.Client.EmuHawk
 
 			var sfd = new SaveFileDialog
 			{
-				FileName = PathManager.FilesystemSafeName(Global.Game) + "-Palettes",
+				FileName = $"{PathManager.FilesystemSafeName(Global.Game)}-Palettes",
 				InitialDirectory = path,
 				Filter = "PNG (*.png)|*.png|Bitmap (*.bmp)|*.bmp|All Files|*.*",
 				RestoreDirectory = true

BizHawk.Client.EmuHawk/config/GB/ColorChooserForm.cs

@@ -353,7 +353,7 @@ namespace BizHawk.Client.EmuHawk
 			using (var sfd = new SaveFileDialog())
 			{
 				sfd.InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries["GB", "Palettes"].Path, "GB");
-				sfd.FileName = Global.Game.Name + ".pal";
+				sfd.FileName = $"{Global.Game.Name}.pal";
 
 				sfd.Filter = "Gambatte Palettes (*.pal)|*.pal|All Files|*.*";
 				sfd.RestoreDirectory = true;

BizHawk.Client.EmuHawk/config/InputCompositeWidget.cs

@@ -38,13 +38,13 @@ namespace BizHawk.Client.EmuHawk
 
 		public void RefreshTooltip()
 		{
-			string widgetText = "Current Binding: " + widget.Text;
+			string widgetText = $"Current Binding: {widget.Text}";
 			if (_bindingTooltipText != null)
 			{
-				widgetText = widgetText + "\r\n---\r\n" + _bindingTooltipText;
+				widgetText = $"{widgetText}\r\n---\r\n{_bindingTooltipText}";
 			}
 
-			widgetText = widgetText + "\r\n---\r\n" + WidgetTooltipText;
+			widgetText = $"{widgetText}\r\n---\r\n{WidgetTooltipText}";
 			_tooltip.SetToolTip(widget, widgetText);
 		}
 

BizHawk.Client.EmuHawk/config/MessageConfig.cs

@@ -411,15 +411,15 @@ namespace BizHawk.Client.EmuHawk
 				_dispAutoholdy = _py;
 			}
 
-			FpsPosLabel.Text = _dispFpSx + ", " + _dispFpSy;
+			FpsPosLabel.Text = $"{_dispFpSx}, {_dispFpSy}";
-			FCLabel.Text = _dispFrameCx + ", " + _dispFrameCy;
+			FCLabel.Text = $"{_dispFrameCx}, {_dispFrameCy}";
-			LagLabel.Text = _dispLagx + ", " + _dispLagy;
+			LagLabel.Text = $"{_dispLagx}, {_dispLagy}";
-			InpLabel.Text = _dispInpx + ", " + _dispInpy;
+			InpLabel.Text = $"{_dispInpx}, {_dispInpy}";
-			WatchesLabel.Text = _dispWatchesx + ", " + _dispWatchesy;
+			WatchesLabel.Text = $"{_dispWatchesx}, {_dispWatchesy}";
-			RerecLabel.Text = _dispRecx + ", " + _dispRecy;
+			RerecLabel.Text = $"{_dispRecx}, {_dispRecy}";
-			MultitrackLabel.Text = _dispMultix + ", " + _dispMultiy;
+			MultitrackLabel.Text = $"{_dispMultix}, {_dispMultiy}";
-			MessLabel.Text = _dispMessagex + ", " + _dispMessagey;
+			MessLabel.Text = $"{_dispMessagex}, {_dispMessagey}";
-			AutoholdLabel.Text = _dispAutoholdx + ", " + _dispAutoholdy;
+			AutoholdLabel.Text = $"{_dispAutoholdx}, {_dispAutoholdy}";
 		}
 
 		private void ResetDefaultsButton_Click(object sender, EventArgs e)

BizHawk.Client.EmuHawk/config/N64/N64ControllerSettingControl.cs

@@ -16,7 +16,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			InitializeComponent();
 
-			ControllerNameLabel.Text = "Controller " + ControllerNumber;
+			ControllerNameLabel.Text = $"Controller {ControllerNumber}";
 		}
 
 		public int ControllerNumber
@@ -82,7 +82,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public override void Refresh()
 		{
-			ControllerNameLabel.Text = "Controller " + ControllerNumber;
+			ControllerNameLabel.Text = $"Controller {ControllerNumber}";
 			base.Refresh();
 		}
 

BizHawk.Client.EmuHawk/config/N64/N64VideoPluginconfig.cs

@@ -533,9 +533,7 @@ namespace BizHawk.Client.EmuHawk
 			VideoResolutionXTextBox.Text = _s.VideoSizeX.ToString();
 			VideoResolutionYTextBox.Text = _s.VideoSizeY.ToString();
 
-			var videoSetting = _s.VideoSizeX
+			var videoSetting = $"{_s.VideoSizeX} x {_s.VideoSizeY}";
-						+ " x "
-						+ _s.VideoSizeY;
 
 			var index = VideoResolutionComboBox.Items.IndexOf(videoSetting);
 			if (index >= 0)
@@ -605,7 +603,7 @@ namespace BizHawk.Client.EmuHawk
 			RiceColorQuality_Combo.SelectedIndex = _ss.RicePlugin.ColorQuality;
 			RiceOpenGLRenderSetting_Combo.SelectedIndex = _ss.RicePlugin.OpenGLRenderSetting;
 			RiceAnisotropicFiltering_TB.Value = _ss.RicePlugin.AnisotropicFiltering;
-			AnisotropicFiltering_LB.Text = "Anisotropic Filtering: " + RiceAnisotropicFiltering_TB.Value;
+			AnisotropicFiltering_LB.Text = $"Anisotropic Filtering: {RiceAnisotropicFiltering_TB.Value}";
 
 			RiceUseDefaultHacks_CB.Checked = _ss.RicePlugin.UseDefaultHacks;
 
@@ -854,7 +852,7 @@ namespace BizHawk.Client.EmuHawk
 		
 		private void RiceAnisotropicFiltering_Tb_Scroll_1(object sender, EventArgs e)
 		{
-			AnisotropicFiltering_LB.Text = "Anisotropic Filtering: " + RiceAnisotropicFiltering_TB.Value;
+			AnisotropicFiltering_LB.Text = $"Anisotropic Filtering: {RiceAnisotropicFiltering_TB.Value}";
 		}
 
 		private void RiceUseDefaultHacks_Cb_CheckedChanged(object sender, EventArgs e)

BizHawk.Client.EmuHawk/config/NES/NESGraphicsConfig.cs

@@ -113,7 +113,7 @@ namespace BizHawk.Client.EmuHawk
 						var data = Palettes.Load_FCEUX_Palette(HawkFile.ReadAllBytes(palette.Name));
 						if (showmsg)
 						{
-							GlobalWin.OSD.AddMessage("Palette file loaded: " + palette.Name);
+							GlobalWin.OSD.AddMessage($"Palette file loaded: {palette.Name}");
 						}
 
 						return data;

BizHawk.Client.EmuHawk/config/PSX/PSXControllerConfigNew.cs

@@ -113,7 +113,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				else
 				{
-					lbl.Text = "P" + lc.PlayerAssignments[i];
+					lbl.Text = $"P{lc.PlayerAssignments[i]}";
 					lbl.Visible = true;
 				}
 			}

BizHawk.Client.EmuHawk/config/PathConfig.cs

@@ -220,7 +220,7 @@ namespace BizHawk.Client.EmuHawk
 
 			var f = new FolderBrowserEx
 			{
-				Description = "Set the directory for " + name,
+				Description = $"Set the directory for {name}",
 				SelectedPath = PathManager.MakeAbsolutePath(box.Text, system)
 			};
 			var result = f.ShowDialog();

BizHawk.Client.EmuHawk/config/RewindConfig.cs

@@ -23,7 +23,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (Global.Rewinder.HasBuffer)
 			{
-				FullnessLabel.Text = $"{Global.Rewinder.FullnessRatio * 100:0.00}" + "%";
+				FullnessLabel.Text = $"{Global.Rewinder.FullnessRatio * 100:0.00}%";
 				RewindFramesUsedLabel.Text = Global.Rewinder.Count.ToString();
 			}
 			else
@@ -94,10 +94,10 @@ namespace BizHawk.Client.EmuHawk
 			if (num >= 1024)
 			{
 				num /= 1024.0;
-				return $"{num:0.00}" + " MB";
+				return $"{num:0.00} MB";
 			}
 
-			return $"{num:0.00}" + " KB";
+			return $"{num:0.00} KB";
 		}
 
 		private void SetStateSize()
@@ -344,8 +344,8 @@ namespace BizHawk.Client.EmuHawk
 			double minutes = estTotalFrames / 60 / 60;
 
 			AverageStoredStateSizeLabel.Text = FormatKB(avgStateSize);
-			ApproxFramesLabel.Text = $"{estFrames:n0}" + " frames";
+			ApproxFramesLabel.Text = $"{estFrames:n0} frames";
-			EstTimeLabel.Text = $"{minutes:n}" + " minutes";
+			EstTimeLabel.Text = $"{minutes:n} minutes";
 		}
 
 		private void BufferSizeUpDown_ValueChanged(object sender, EventArgs e)

BizHawk.Client.EmuHawk/movie/EditSubtitlesForm.cs

@@ -46,8 +46,8 @@ namespace BizHawk.Client.EmuHawk
 		private void ShowError(int row, int column)
 		{
 			var c = SubGrid.Rows[row].Cells[column];
-			var error = "Unable to parse value: " + c.Value;
+			var error = $"Unable to parse value: {c.Value}";
-			var caption = "Parse Error Row " + row + " Column " + column;
+			var caption = $"Parse Error Row {row} Column {column}";
 			MessageBox.Show(error, caption, MessageBoxButtons.OK, MessageBoxIcon.Error);
 		}
 
@@ -104,7 +104,7 @@ namespace BizHawk.Client.EmuHawk
 				c = SubGrid.Rows[x].Cells[3];
 				c.Value = s.Duration;
 				c = SubGrid.Rows[x].Cells[4];
-				c.Value = string.Format("{0:X8}", s.Color);
+				c.Value = $"{s.Color:X8}";
 				c.Style.BackColor = Color.FromArgb((int)s.Color);
 				c = SubGrid.Rows[x].Cells[5];
 				c.Value = s.Message;
@@ -127,7 +127,7 @@ namespace BizHawk.Client.EmuHawk
 			c = SubGrid.Rows[index].Cells[3];
 			c.Value = s.Duration;
 			c = SubGrid.Rows[index].Cells[4];
-			c.Value = string.Format("{0:X8}", s.Color);
+			c.Value = $"{s.Color:X8}";
 			c.Style.BackColor = Color.FromArgb((int)s.Color);
 			c = SubGrid.Rows[index].Cells[5];
 			c.Value = s.Message;
@@ -229,9 +229,7 @@ namespace BizHawk.Client.EmuHawk
 			File.WriteAllText(fileName, str);
 
 			// Display success
-			MessageBox.Show(
+			MessageBox.Show($"Subtitles succesfully exported to {fileName}.", "Success");
-				string.Format("Subtitles succesfully exported to {0}.", fileName),
-				"Success");
 		}
 
 		private void SubGrid_DefaultValuesNeeded(object sender, DataGridViewRowEventArgs e)

BizHawk.Client.EmuHawk/movie/PlayMovie.cs

@@ -154,8 +154,7 @@ namespace BizHawk.Client.EmuHawk
 		private void UpdateList()
 		{
 			MovieView.Refresh();
-			MovieCount.Text = _movieList.Count + " movie"
+			MovieCount.Text = $"{_movieList.Count} {(_movieList.Count == 1 ? "movie" : "movies")}";
-				+ (_movieList.Count != 1 ? "s" : "");
 		}
 
 		private void PreHighlightMovie()
@@ -193,7 +192,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				foreach (var ext in MovieService.MovieExtensions)
 				{
-					if (Path.GetExtension(_movieList[indices[i]].Filename).ToUpper() == "." + ext)
+					if (Path.GetExtension(_movieList[indices[i]].Filename).ToUpper() == $".{ext}")
 					{
 						tas.Add(i);
 					}
@@ -266,8 +265,8 @@ namespace BizHawk.Client.EmuHawk
 				}
 
 				// add movies
-				fpTodo.AddRange(Directory.GetFiles(dp, "*." + MovieService.DefaultExtension));
+				fpTodo.AddRange(Directory.GetFiles(dp, $"*.{MovieService.DefaultExtension}"));
-				fpTodo.AddRange(Directory.GetFiles(dp, "*." + TasMovie.Extension));
+				fpTodo.AddRange(Directory.GetFiles(dp, $"*.{TasMovie.Extension}"));
 			}
 
 			// in parallel, scan each movie
@@ -419,7 +418,7 @@ namespace BizHawk.Client.EmuHawk
 						if (kvp.Value != Global.Game.Hash)
 						{
 							item.BackColor = Color.Pink;
-							toolTip1.SetToolTip(DetailsView, "Current SHA1: " + Global.Game.Hash);
+							toolTip1.SetToolTip(DetailsView, $"Current SHA1: {Global.Game.Hash}");
 						}
 						break;
 					case HeaderKeys.EMULATIONVERSION:
@@ -447,7 +446,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			var FpsItem = new ListViewItem("Fps");
-			FpsItem.SubItems.Add(string.Format("{0:0.#######}", Fps(_movieList[firstIndex])));
+			FpsItem.SubItems.Add($"{Fps(_movieList[firstIndex]):0.#######}");
 			DetailsView.Items.Add(FpsItem);
 
 			var FramesItem = new ListViewItem("Frames");
@@ -576,9 +575,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var ofd = new OpenFileDialog
 			{
-				Filter = "Movie Files (*." + MovieService.DefaultExtension + ")|*." + MovieService.DefaultExtension +
+				Filter = $"Movie Files (*.{MovieService.DefaultExtension})|*.{MovieService.DefaultExtension}|TAS project Files (*.{TasMovie.Extension})|*.{TasMovie.Extension}|All Files|*.*",
-					"|TAS project Files (*." + TasMovie.Extension + ")|*." + TasMovie.Extension +
-					"|All Files|*.*",
 				InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries.MoviesPathFragment, null)
 			};
 

BizHawk.Client.EmuHawk/movie/RecordMovie.cs

@@ -61,7 +61,7 @@ namespace BizHawk.Client.EmuHawk
 					if (!MovieService.MovieExtensions.Contains(Path.GetExtension(path)))
 					{
 						// If no valid movie extension, add movie extension
-						path += "." + MovieService.DefaultExtension;
+						path += $".{MovieService.DefaultExtension}";
 					}
 				}
 			}
@@ -77,7 +77,7 @@ namespace BizHawk.Client.EmuHawk
 				var test = new FileInfo(path);
 				if (test.Exists)
 				{
-					var result = MessageBox.Show(path + " already exists, overwrite?", "Confirm overwrite", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning);
+					var result = MessageBox.Show($"{path} already exists, overwrite?", "Confirm overwrite", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning);
 					if (result == DialogResult.Cancel)
 					{
 						return;
@@ -180,10 +180,10 @@ namespace BizHawk.Client.EmuHawk
 			var sfd = new SaveFileDialog
 			{
 				InitialDirectory = movieFolderPath,
-				DefaultExt = "." + Global.MovieSession.Movie.PreferredExtension,
+				DefaultExt = $".{Global.MovieSession.Movie.PreferredExtension}",
 				FileName = RecordBox.Text,
 				OverwritePrompt = false,
-				Filter = "Movie Files (*." + Global.MovieSession.Movie.PreferredExtension + ")|*." + Global.MovieSession.Movie.PreferredExtension + "|All Files|*.*"
+				Filter = $"Movie Files (*.{Global.MovieSession.Movie.PreferredExtension})|*.{Global.MovieSession.Movie.PreferredExtension}|All Files|*.*"
 			};
 
 			var result = sfd.ShowHawkDialog();

BizHawk.Client.EmuHawk/tools/BasicBot/BasicBot.cs

@@ -27,7 +27,7 @@ namespace BizHawk.Client.EmuHawk
 
 				if (!string.IsNullOrWhiteSpace(_currentFileName))
 				{
-					Text = DialogTitle + " - " + Path.GetFileNameWithoutExtension(_currentFileName);
+					Text = $"{DialogTitle} - {Path.GetFileNameWithoutExtension(_currentFileName)}";
 				}
 				else
 				{
@@ -125,7 +125,7 @@ namespace BizHawk.Client.EmuHawk
 					.ToString()
 					.Last();
 
-				return "QuickSave" + num;
+				return $"QuickSave{num}";
 			}
 		}
 
@@ -772,7 +772,7 @@ namespace BizHawk.Client.EmuHawk
 
 			CurrentFileName = path;
 			Settings.RecentBotFiles.Add(CurrentFileName);
-			MessageLabel.Text = Path.GetFileNameWithoutExtension(path) + " loaded";
+			MessageLabel.Text = $"{Path.GetFileNameWithoutExtension(path)} loaded";
 
 			AssessRunButtonStatus();
 			return true;
@@ -814,7 +814,7 @@ namespace BizHawk.Client.EmuHawk
 			File.WriteAllText(path, json);
 			CurrentFileName = path;
 			Settings.RecentBotFiles.Add(CurrentFileName);
-			MessageLabel.Text = Path.GetFileName(CurrentFileName) + " saved";
+			MessageLabel.Text = $"{Path.GetFileName(CurrentFileName)} saved";
 		}
 
 		#endregion

BizHawk.Client.EmuHawk/tools/BatchRun.cs

@@ -33,7 +33,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void SetCount()
 		{
-			label2.Text = string.Format("Number of files: {0}", listBox1.Items.Count);
+			label2.Text = $"Number of files: {listBox1.Items.Count}";
 		}
 
 		private void listBox1_DragDrop(object sender, DragEventArgs e)

BizHawk.Client.EmuHawk/tools/BatchRunner.cs

@@ -81,12 +81,12 @@ namespace BizHawk.Client.EmuHawk
 		void OnLoadError(object sender, RomLoader.RomErrorArgs e)
 		{
 			current.Status = Result.EStatus.ErrorOnLoad;
-			current.Messages.Add(string.Format("OnLoadError: {0}, {1}, {2}", e.AttemptedCoreLoad, e.Message, e.Type.ToString()));
+			current.Messages.Add($"OnLoadError: {e.AttemptedCoreLoad}, {e.Message}, {e.Type.ToString()}");
 		}
 
 		void CommMessage(string msg)
 		{
-			current.Messages.Add(string.Format("CommMessage: {0}", msg));
+			current.Messages.Add($"CommMessage: {msg}");
 		}
 
 		int? ChooseArchive(HawkFile hf)

BizHawk.Client.EmuHawk/tools/CDL.cs

@@ -38,7 +38,7 @@ namespace BizHawk.Client.EmuHawk
 			_currentFilename = fname;
 			if (_currentFilename == null)
 				Text = "Code Data Logger";
-			else Text = string.Format("Code Data Logger - {0}", fname);
+			else Text = $"Code Data Logger - {fname}";
 		}
 
 		[RequiredService]
@@ -147,29 +147,29 @@ namespace BizHawk.Client.EmuHawk
 				long addr = bm[kvp.Key];
 
 				var lvi = listContents[idx++] = new string[13];
-				lvi[0] = string.Format("{0:X8}", addr);
+				lvi[0] = $"{addr:X8}";
 				lvi[1] = kvp.Key;
-				lvi[2] = string.Format("{0:0.00}%", total / (float)kvp.Value.Length * 100f);
+				lvi[2] = $"{total / (float)kvp.Value.Length * 100f:0.00}%";
 				if (tsbViewStyle.SelectedIndex == 2)
-					lvi[3] = string.Format("{0:0.00}", total / 1024.0f);
+					lvi[3] = $"{total / 1024.0f:0.00}";
 				else
-					lvi[3] = string.Format("{0}", total);
+					lvi[3] = $"{total}";
 				if (tsbViewStyle.SelectedIndex == 2)
 				{
 					int n = (int)(kvp.Value.Length / 1024.0f);
 					float ncheck = kvp.Value.Length / 1024.0f;
-					lvi[4] = string.Format("of {0}{1} KBytes", n == ncheck ? "" : "~", n);
+					lvi[4] = $"of {(n == ncheck ? "" : "~")}{n} KBytes";
 				}
 				else
-					lvi[4] = string.Format("of {0} Bytes", kvp.Value.Length);
+					lvi[4] = $"of {kvp.Value.Length} Bytes";
 				for (int i = 0; i < 8; i++)
 				{
 					if (tsbViewStyle.SelectedIndex == 0)
-						lvi[5 + i] = string.Format("{0:0.00}%", totals[i] / (float)kvp.Value.Length * 100f);
+						lvi[5 + i] = $"{totals[i] / (float)kvp.Value.Length * 100f:0.00}%";
 					if (tsbViewStyle.SelectedIndex == 1)
-						lvi[5 + i] = string.Format("{0}", totals[i]);
+						lvi[5 + i] = $"{totals[i]}";
 					if (tsbViewStyle.SelectedIndex == 2)
-						lvi[5 + i] = string.Format("{0:0.00}", totals[i] / 1024.0f);
+						lvi[5 + i] = $"{totals[i] / 1024.0f:0.00}";
 				}
 
 			}
@@ -498,7 +498,7 @@ namespace BizHawk.Client.EmuHawk
 				try
 				{
 					autoloading = true;
-					var autoresume_file = PathManager.FilesystemSafeName(Global.Game) + ".cdl";
+					var autoresume_file = $"{PathManager.FilesystemSafeName(Global.Game)}.cdl";
 					var autoresume_dir = PathManager.MakeAbsolutePath(Global.Config.PathEntries.LogPathFragment, null);
 					var autoresume_path = Path.Combine(autoresume_dir, autoresume_file);
 					if (File.Exists(autoresume_path))

BizHawk.Client.EmuHawk/tools/Cheats/CheatEdit.cs

@@ -349,7 +349,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			else
 			{
-				MessageBox.Show(address + " is not a valid address for the domain " + domain.Name, "Index out of range", MessageBoxButtons.OK, MessageBoxIcon.Warning);
+				MessageBox.Show($"{address} is not a valid address for the domain {domain.Name}", "Index out of range", MessageBoxButtons.OK, MessageBoxIcon.Warning);
 				return Cheat.Separator;
 			}
 		}

BizHawk.Client.EmuHawk/tools/Cheats/Cheats.cs

@@ -81,9 +81,7 @@ namespace BizHawk.Client.EmuHawk
 		public void UpdateDialog()
 		{
 			CheatListView.ItemCount = Global.CheatList.Count;
-			TotalLabel.Text = Global.CheatList.CheatCount
+			TotalLabel.Text = $"{Global.CheatList.CheatCount} {(Global.CheatList.CheatCount == 1 ? "cheat" : "cheats")} {Global.CheatList.ActiveCount} active";
-				+ (Global.CheatList.CheatCount == 1 ? " cheat " : " cheats ")
-				+ Global.CheatList.ActiveCount + " active";
 		}
 
 		private void LoadFileFromRecent(string path)
@@ -107,9 +105,11 @@ namespace BizHawk.Client.EmuHawk
 
 		private void UpdateMessageLabel(bool saved = false)
 		{
-			MessageLabel.Text = saved 
+			MessageLabel.Text = saved
-				? Path.GetFileName(Global.CheatList.CurrentFileName) + " saved."
+				? $"{Path.GetFileName(Global.CheatList.CurrentFileName)} saved."
-				: Path.GetFileName(Global.CheatList.CurrentFileName) + (Global.CheatList.Changes ? " *" : "");
+				: Global.CheatList.Changes
+					? $"{Path.GetFileName(Global.CheatList.CurrentFileName)} *"
+					: Path.GetFileName(Global.CheatList.CurrentFileName);
 		}
 
 		public bool AskSaveChanges()
@@ -331,7 +331,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					var cheat = SelectedCheats.First();
 					CheatEditor.SetCheat(cheat);
-					CheatGroupBox.Text = "Editing Cheat " + cheat.Name + " - " + cheat.AddressStr;
+					CheatGroupBox.Text = $"Editing Cheat {cheat.Name} - {cheat.AddressStr}";
 				}
 				else
 				{

BizHawk.Client.EmuHawk/tools/Debugger/GenericDebugger.Disassembler.cs

@@ -75,7 +75,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				if (column == 0)
 				{
-					text = string.Format("{0:X" + _pcRegisterSize + "}", _disassemblyLines[index].Address);
+					text = string.Format($"{{0:X{_pcRegisterSize}}}", _disassemblyLines[index].Address);
 				}
 				else if (column == 1)
 				{
@@ -206,7 +206,7 @@ namespace BizHawk.Client.EmuHawk
 						blob.AppendLine();
 					}
 
-					blob.Append(string.Format("{0:X" + _pcRegisterSize + "}", _disassemblyLines[index].Address))
+					blob.Append(string.Format($"{{0:X{_pcRegisterSize}}}", _disassemblyLines[index].Address))
 						.Append(" ")
 						.Append(_disassemblyLines[index].Mnemonic);
 				}

BizHawk.Client.EmuHawk/tools/GB/GBGPUView.cs

@@ -52,7 +52,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				_spriteback = Color.FromArgb(255, value); // force fully opaque
 				panelSpriteBackColor.BackColor = _spriteback;
-				labelSpriteBackColor.Text = string.Format("({0},{1},{2})", _spriteback.R, _spriteback.G, _spriteback.B);
+				labelSpriteBackColor.Text = $"({_spriteback.R},{_spriteback.G},{_spriteback.B})";
 			}
 		}
 
@@ -634,9 +634,9 @@ namespace BizHawk.Client.EmuHawk
 				int* pal = (int*)(sprite ? _sppal : _bgpal) + x * 4;
 				int color = pal[y];
 
-				sb.AppendLine(string.Format("Palette {0}", x));
+				sb.AppendLine($"Palette {x}");
-				sb.AppendLine(string.Format("Color {0}", y));
+				sb.AppendLine($"Color {y}");
-				sb.AppendLine(string.Format("(R,G,B) = ({0},{1},{2})", color >> 16 & 255, color >> 8 & 255, color & 255));
+				sb.AppendLine($"(R,G,B) = ({color >> 16 & 255},{color >> 8 & 255},{color & 255})");
 
 				var lockdata = bmpViewDetails.BMP.LockBits(new Rectangle(0, 0, 8, 10), System.Drawing.Imaging.ImageLockMode.WriteOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
 				int* dest = (int*)lockdata.Scan0;
@@ -679,9 +679,9 @@ namespace BizHawk.Client.EmuHawk
 				int tileindex = y * 16 + x;
 				int tileoffs = tileindex * 16;
 				if (_cgb)
-					sb.AppendLine(string.Format("Tile #{0} @{2}:{1:x4}", tileindex, tileoffs + 0x8000, secondbank ? 1 : 0));
+					sb.AppendLine($"Tile #{tileindex} @{(secondbank ? 1 : 0)}:{tileoffs + 0x8000:x4}");
 				else
-					sb.AppendLine(string.Format("Tile #{0} @{1:x4}", tileindex, tileoffs + 0x8000));
+					sb.AppendLine($"Tile #{tileindex} @{tileoffs + 0x8000:x4}");
 
 				var lockdata = bmpViewDetails.BMP.LockBits(new Rectangle(0, 0, 8, 8), System.Drawing.Imaging.ImageLockMode.WriteOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
 				DrawTile((byte*)_vram + tileoffs + (secondbank ? 8192 : 0), (int*)lockdata.Scan0, lockdata.Stride / sizeof(int), (int*)tilespal);
@@ -718,18 +718,18 @@ namespace BizHawk.Client.EmuHawk
 				var lockdata = bmpViewDetails.BMP.LockBits(new Rectangle(0, 0, 8, 8), System.Drawing.Imaging.ImageLockMode.WriteOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
 				if (!_cgb)
 				{
-					sb.AppendLine(string.Format("{0} Map ({1},{2}) @{3:x4}", win ? "Win" : "BG", x, y, mapoffs + 0x8000));
+					sb.AppendLine($"{(win ? "Win" : "BG")} Map ({x},{y}) @{mapoffs + 0x8000:x4}");
-					sb.AppendLine(string.Format("  Tile #{0} @{1:x4}", tileindex, tileoffs + 0x8000));
+					sb.AppendLine($"  Tile #{tileindex} @{tileoffs + 0x8000:x4}");
 					DrawTile((byte*)_vram + tileoffs, (int*)lockdata.Scan0, lockdata.Stride / sizeof(int), (int*)_bgpal);
 				}
 				else
 				{
 					int tileext = mapbase[8192];
 
-					sb.AppendLine(string.Format("{0} Map ({1},{2}) @{3:x4}", win ? "Win" : "BG", x, y, mapoffs + 0x8000));
+					sb.AppendLine($"{(win ? "Win" : "BG")} Map ({x},{y}) @{mapoffs + 0x8000:x4}");
-					sb.AppendLine(string.Format("  Tile #{0} @{2}:{1:x4}", tileindex, tileoffs + 0x8000, tileext.Bit(3) ? 1 : 0));
+					sb.AppendLine($"  Tile #{tileindex} @{(tileext.Bit(3) ? 1 : 0)}:{tileoffs + 0x8000:x4}");
-					sb.AppendLine(string.Format("  Palette {0}", tileext & 7));
+					sb.AppendLine($"  Palette {tileext & 7}");
-					sb.AppendLine(string.Format("  Flags {0}{1}{2}", tileext.Bit(5) ? 'H' : ' ', tileext.Bit(6) ? 'V' : ' ', tileext.Bit(7) ? 'P' : ' '));
+					sb.AppendLine($"  Flags {(tileext.Bit(5) ? 'H' : ' ')}{(tileext.Bit(6) ? 'V' : ' ')}{(tileext.Bit(7) ? 'P' : ' ')}");
 					DrawTileHv((byte*)_vram + tileoffs + (tileext.Bit(3) ? 8192 : 0), (int*)lockdata.Scan0, lockdata.Stride / sizeof(int), (int*)_bgpal + 4 * (tileext & 7), tileext.Bit(5), tileext.Bit(6));
 				}
 				bmpViewDetails.BMP.UnlockBits(lockdata);
@@ -765,26 +765,26 @@ namespace BizHawk.Client.EmuHawk
 				if (tall)
 					tilenum = vflip ? tilenum | 1 : tilenum & ~1;
 				int tileoffs = tilenum * 16;
-				sb.AppendLine(string.Format("Sprite #{0} @{1:x4}", x, 4 * x + 0xfe00));
+				sb.AppendLine($"Sprite #{x} @{4 * x + 0xfe00:x4}");
-				sb.AppendLine(string.Format("  (x,y) = ({0},{1})", sx, sy));
+				sb.AppendLine($"  (x,y) = ({sx},{sy})");
 				var lockdata = bmpViewDetails.BMP.LockBits(new Rectangle(0, 0, 8, tall ? 16 : 8), System.Drawing.Imaging.ImageLockMode.WriteOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
 				if (_cgb)
 				{
-					sb.AppendLine(string.Format("  Tile #{0} @{2}:{1:x4}", y == 1 ? tilenum ^ 1 : tilenum, tileoffs + 0x8000, flags.Bit(3) ? 1 : 0));
+					sb.AppendLine($"  Tile #{(y == 1 ? tilenum ^ 1 : tilenum)} @{(flags.Bit(3) ? 1 : 0)}:{tileoffs + 0x8000:x4}");
-					sb.AppendLine(string.Format("  Palette {0}", flags & 7));
+					sb.AppendLine($"  Palette {flags & 7}");
 					DrawTileHv((byte*)_vram + tileoffs + (flags.Bit(3) ? 8192 : 0), (int*)lockdata.Scan0, lockdata.Stride / sizeof(int), (int*)_sppal + 4 * (flags & 7), hflip, vflip);
 					if (tall)
 						DrawTileHv((byte*)_vram + (tileoffs ^ 16) + (flags.Bit(3) ? 8192 : 0), (int*)(lockdata.Scan0 + lockdata.Stride * 8), lockdata.Stride / sizeof(int), (int*)_sppal + 4 * (flags & 7), hflip, vflip);
 				}
 				else
 				{
-					sb.AppendLine(string.Format("  Tile #{0} @{1:x4}", y == 1 ? tilenum ^ 1 : tilenum, tileoffs + 0x8000));
+					sb.AppendLine($"  Tile #{(y == 1 ? tilenum ^ 1 : tilenum)} @{tileoffs + 0x8000:x4}");
-					sb.AppendLine(string.Format("  Palette {0}", flags.Bit(4) ? 1 : 0));
+					sb.AppendLine($"  Palette {(flags.Bit(4) ? 1 : 0)}");
 					DrawTileHv((byte*)_vram + tileoffs, (int*)lockdata.Scan0, lockdata.Stride / sizeof(int), (int*)_sppal + (flags.Bit(4) ? 4 : 0), hflip, vflip);
 					if (tall)
 						DrawTileHv((byte*)_vram + (tileoffs ^ 16), (int*)(lockdata.Scan0 + lockdata.Stride * 8), lockdata.Stride / sizeof(int), (int*)_sppal + 4 * (flags.Bit(4) ? 4 : 0), hflip, vflip);
 				}
-				sb.AppendLine(string.Format("  Flags {0}{1}{2}", hflip ? 'H' : ' ', vflip ? 'V' : ' ', flags.Bit(7) ? 'P' : ' '));
+				sb.AppendLine($"  Flags {(hflip ? 'H' : ' ')}{(vflip ? 'V' : ' ')}{(flags.Bit(7) ? 'P' : ' ')}");
 				bmpViewDetails.BMP.UnlockBits(lockdata);
 				labelDetails.Text = sb.ToString();
 				bmpViewDetails.Refresh();
@@ -946,7 +946,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					var bv = found as BmpView;
 					Clipboard.SetImage(bv.BMP);
-					labelClipboard.Text = found.Text + " copied to clipboard.";
+					labelClipboard.Text = $"{found.Text} copied to clipboard.";
 					_messagetimer.Stop();
 					_messagetimer.Start();
 				}

BizHawk.Client.EmuHawk/tools/GB/GBGameGenie.cs

@@ -458,17 +458,17 @@ namespace BizHawk.Client.EmuHawk
 					GBGGDecode(GGCodeMaskBox.Text, ref val, ref add, ref cmp);
 					if (add > -1)
 					{
-						AddressBox.Text = string.Format("{0:X4}", add);
+						AddressBox.Text = $"{add:X4}";
 					}
 
 					if (val > -1)
 					{
-						ValueBox.Text = string.Format("{0:X2}", val);
+						ValueBox.Text = $"{val:X2}";
 					}
 
 					if (cmp > -1)
 					{
-						CompareBox.Text = string.Format("{0:X2}", cmp);
+						CompareBox.Text = $"{cmp:X2}";
 					}
 					else
 					{

BizHawk.Client.EmuHawk/tools/GBA/GBAGPUView.cs

@@ -790,7 +790,7 @@ namespace BizHawk.Client.EmuHawk
 		private void hScrollBar1_ValueChanged(object sender, EventArgs e)
 		{
 			_cbscanline = (hScrollBar1.Value + 160) % 228;
-			radioButtonScanline.Text = "Scanline " + _cbscanline;
+			radioButtonScanline.Text = $"Scanline {_cbscanline}";
 		}
 
 		private void radioButtonManual_CheckedChanged(object sender, EventArgs e)
@@ -838,7 +838,7 @@ namespace BizHawk.Client.EmuHawk
 				if (found is BmpView)
 				{
 					Clipboard.SetImage((found as BmpView).BMP);
-					labelClipboard.Text = found.Text + " copied to clipboard.";
+					labelClipboard.Text = $"{found.Text} copied to clipboard.";
 					timerMessage.Stop();
 					timerMessage.Start();
 				}

BizHawk.Client.EmuHawk/tools/GameShark.cs

@@ -311,9 +311,9 @@ namespace BizHawk.Client.EmuHawk
 				int cmp = 0;
 				parseString = SingleCheat.Replace("-", "");
 				GBGGDecode(parseString, ref val, ref add, ref cmp);
-				RAMAddress = string.Format("{0:X4}", add);
+				RAMAddress = $"{add:X4}";
-				RAMValue = string.Format("{0:X2}", val);
+				RAMValue = $"{val:X2}";
-				RAMCompare = string.Format("{0:X2}", cmp);
+				RAMCompare = $"{cmp:X2}";
 			}
 			//Game Genie
 			else if (SingleCheat.Contains("-") == true && SingleCheat.LastIndexOf("-") != 7 && SingleCheat.IndexOf("-") != 3)
@@ -382,7 +382,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		//Provided by mGBA and endrift
@@ -457,8 +457,8 @@ namespace BizHawk.Client.EmuHawk
 						//op1 has the Address
 						//op2 has the Value
 						//Sum, is pointless?
-						RAMAddress = string.Format("{0:X8}", op1);
+						RAMAddress = $"{op1:X8}";
-						RAMValue = string.Format("{0:X8}", op2);
+						RAMValue = $"{op2:X8}";
 						GBAGameShark();
 					}
 					//We don't do Else If after the if here because it won't allow us to verify the second code check.
@@ -492,8 +492,8 @@ namespace BizHawk.Client.EmuHawk
 						//op1 has the Address
 						//op2 has the Value
 						//Sum, is pointless?
-						RAMAddress = string.Format("{0:X8}", op1);
+						RAMAddress = $"{op1:X8}";
-						RAMValue = string.Format("{0:X8}", op2);
+						RAMValue = $"{op2:X8}";
 						blnEncrypted = true;
 						GBAActionReplay();
 					}
@@ -560,9 +560,9 @@ namespace BizHawk.Client.EmuHawk
 					//	//op1 has the Address
 					//	//op2 has the Value
 					//	//Sum, is pointless?
-					//	RAMAddress = string.Format("{0:X8}", op1);
+					//	RAMAddress = $"{op1:X8}";
 					//	//RAMAddress = RAMAddress.Remove(0, 1);
-					//	RAMValue = string.Format("{0:X8}", op2);
+					//	RAMValue = $"{op2:X8}";
 					//	// && RAMAddress[6] == '0'
 					//}
 
@@ -2052,12 +2052,12 @@ namespace BizHawk.Client.EmuHawk
 				string RealAddress = null;
 				string realValue = null;
 				RealAddress = RAMValue.Remove(0, 1);
-				//MessageBox.Show("Real Address: " + RealAddress);
+				//MessageBox.Show($"Real Address: {RealAddress}");
 				//We need the next line
 				try
 				{
 					loopValue += 1;
-					//MessageBox.Show("Loop Value: " + loopValue.ToString());
+					//MessageBox.Show($"Loop Value: {loopValue}");
 					SingleCheat = txtCheat.Lines[loopValue].ToUpper();
 					//We need to parse now.
 					if (SingleCheat.Length == 17 && SingleCheat.IndexOf(" ") == 8)
@@ -2087,8 +2087,8 @@ namespace BizHawk.Client.EmuHawk
 							//op1 has the Address
 							//op2 has the Value
 							//Sum, is pointless?
-							RAMAddress = string.Format("{0:X8}", op1);
+							RAMAddress = $"{op1:X8}";
-							RAMValue = string.Format("{0:X8}", op2);
+							RAMValue = $"{op2:X8}";
 						}
 						else if (blnEncrypted == false)
 						{
@@ -2134,7 +2134,7 @@ namespace BizHawk.Client.EmuHawk
 				catch (Exception ex)
 				{
 					//We should warn the user.
-					MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+					MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 				}
 			}
 			else if (RAMAddress.StartsWith("080") == true)
@@ -2563,7 +2563,7 @@ namespace BizHawk.Client.EmuHawk
 				//Someone broke the world?
 				catch (Exception ex)
 				{
-					MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+					MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 				}
 			}
 		}
@@ -2691,7 +2691,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		private void NES()
@@ -2734,9 +2734,9 @@ namespace BizHawk.Client.EmuHawk
 					_NESgameGenieTable.TryGetValue(code[5], out x);
 					Address |= (x & 0x07) << 8;
 					Value |= x & 0x08;
-					RAMAddress = string.Format("{0:X4}", Address);
+					RAMAddress = $"{Address:X4}";
-					RAMValue = string.Format("{0:X2}", Value);
+					RAMValue = $"{Value:X2}";
-					strCompare = string.Format("{0:X2}", Compare);
+					strCompare = $"{Compare:X2}";
 				}
 				else if (SingleCheat.Length == 8)
 				{
@@ -2778,9 +2778,9 @@ namespace BizHawk.Client.EmuHawk
 					_NESgameGenieTable.TryGetValue(code[7], out x);
 					Compare |= (x & 0x07) << 4;
 					Value |= x & 0x08;
-					RAMAddress = string.Format("{0:X4}", Address);
+					RAMAddress = $"{Address:X4}";
-					RAMValue = string.Format("{0:X2}", Value);
+					RAMValue = $"{Value:X2}";
-					strCompare = string.Format("{0:X2}", Compare);
+					strCompare = $"{Compare:X2}";
 				}
 			}
 			if (SingleCheat.Length != 6 && SingleCheat.Length != 8)
@@ -2816,7 +2816,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		private void PSX()
@@ -2927,7 +2927,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 
 		}
@@ -3003,7 +3003,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		//This also handles Game Gear due to shared hardware.  Go figure.
@@ -3018,9 +3018,9 @@ namespace BizHawk.Client.EmuHawk
 				int cmp = 0;
 				parseString = SingleCheat.Replace("-", "");
 				GBGGDecode(parseString, ref val, ref add, ref cmp);
-				RAMAddress = string.Format("{0:X4}", add);
+				RAMAddress = $"{add:X4}";
-				RAMValue = string.Format("{0:X2}", val);
+				RAMValue = $"{val:X2}";
-				RAMCompare = string.Format("{0:X2}", cmp);
+				RAMCompare = $"{cmp:X2}";
 			}
 			//Action Replay
 			else if (SingleCheat.IndexOf("-") == 3 && SingleCheat.Length == 9)
@@ -3063,7 +3063,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		//Original code from adelikat
@@ -3142,8 +3142,8 @@ namespace BizHawk.Client.EmuHawk
 				//We have to remove the - since it will cause issues later on.
 				input = SingleCheat.Replace("-", "");
 				SnesGGDecode(input, ref val, ref add);
-				RAMAddress = string.Format("{0:X6}", add);
+				RAMAddress = $"{add:X6}";
-				RAMValue = string.Format("{0:X2}", val);
+				RAMValue = $"{val:X2}";
 				//We trim the first value here to make it work.
 				RAMAddress = RAMAddress.Remove(0, 1);
 				//Note, it's not actually a byte, but a Word.  However, we are using this to keep from repeating code.
@@ -3203,7 +3203,7 @@ namespace BizHawk.Client.EmuHawk
 			//Someone broke the world?
 			catch (Exception ex)
 			{
-				MessageBox.Show("An Error occured: " + ex.GetType().ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+				MessageBox.Show($"An Error occured: {ex.GetType()}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
 			}
 		}
 		private void btnClear_Click(object sender, EventArgs e)

BizHawk.Client.EmuHawk/tools/Genesis/GenGameGenie.cs

@@ -187,8 +187,8 @@ namespace BizHawk.Client.EmuHawk
 					int val = 0;
 					int add = 0;
 					GenGGDecode(GGCodeMaskBox.Text, ref val, ref add);
-					AddressBox.Text = string.Format("{0:X6}", add);
+					AddressBox.Text = $"{add:X6}";
-					ValueBox.Text = string.Format("{0:X4}", val);
+					ValueBox.Text = $"{val:X4}";
 					AddCheatButton.Enabled = true;
 				}
 				else

BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs

@@ -545,7 +545,7 @@ namespace BizHawk.Client.EmuHawk
 					addrStr.Append("  ");
 				}
 
-				addrStr.AppendLine(_addr.ToHexString(_numDigits) + " |");
+				addrStr.AppendLine($"{_addr.ToHexString(_numDigits)} |");
 			}
 
 			return addrStr.ToString();
@@ -700,9 +700,8 @@ namespace BizHawk.Client.EmuHawk
 
 		private void UpdateGroupBoxTitle()
 		{
-			var addressesString = "0x" + string.Format("{0:X8}", _domain.Size / DataSize).TrimStart('0');
+			var addressesString = "0x" + $"{_domain.Size / DataSize:X8}".TrimStart('0');
-			MemoryViewerBox.Text = Emulator.SystemId + " " + _domain + (_domain.CanPoke() ? "" : " (READ-ONLY)") +
+			MemoryViewerBox.Text = $"{Emulator.SystemId} {_domain}{(_domain.CanPoke() ? string.Empty : " (READ-ONLY)")}  -  {addressesString} addresses";
-				"  -  " + addressesString + " addresses";
 		}
 
 		private void ClearNibbles()
@@ -769,8 +768,7 @@ namespace BizHawk.Client.EmuHawk
 				Text += " - Editing Address 0x" + string.Format(_numDigitsStr, _addressHighlighted);
 				if (_secondaryHighlightedAddresses.Any())
 				{
-					Text += string.Format(" (Selected 0x{0:X})", _secondaryHighlightedAddresses.Count() +
+					Text += $" (Selected 0x{_secondaryHighlightedAddresses.Count() + (_secondaryHighlightedAddresses.Contains(_addressHighlighted) ? 0 : 1):X})";
-						(_secondaryHighlightedAddresses.Contains(_addressHighlighted) ? 0 : 1));
 				}
 			}
 		}
@@ -797,7 +795,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			_numDigits = GetNumDigits(_domain.Size);
-			_numDigitsStr = "{0:X" + _numDigits + "}  ";
+			_numDigitsStr = $"{{0:X{_numDigits}}}  ";
 		}
 
 		private void SetDataSize(int size)
@@ -805,7 +803,7 @@ namespace BizHawk.Client.EmuHawk
 			if (size == 1 || size == 2 || size == 4)
 			{
 				DataSize = size;
-				_digitFormatString = "{0:X" + (DataSize * 2) + "} ";
+				_digitFormatString = $"{{0:X{DataSize * 2}}} ";
 				SetHeader();
 				UpdateGroupBoxTitle();
 				UpdateValues();
@@ -907,7 +905,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				var extension = Path.GetExtension(RomName);
 
-				return "Binary (*" + extension + ")|*" + extension + "|All Files|*.*";
+				return $"Binary (*{extension})|*{extension}|All Files|*.*";
 			}
 			
 			return "Binary (*.bin)|*.bin|All Files|*.*";
@@ -988,7 +986,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (_domain.Name == "File on Disk")
 			{
-				sfd.FileName = Path.GetFileNameWithoutExtension(RomName) + ".txt";
+				sfd.FileName = $"{Path.GetFileNameWithoutExtension(RomName)}.txt";
 			}
 			else
 			{
@@ -1386,7 +1384,7 @@ namespace BizHawk.Client.EmuHawk
 					{
 						for (var j = 0; j < 16; j++)
 						{
-							sb.Append(string.Format("{0:X2} ", _domain.PeekByte((i * 16) + j)));
+							sb.Append($"{_domain.PeekByte((i * 16) + j):X2} ");
 						}
 
 						sb.AppendLine();
@@ -1412,7 +1410,7 @@ namespace BizHawk.Client.EmuHawk
 
 			var ofd = new OpenFileDialog
 			{
-				FileName = Path.GetFileNameWithoutExtension(romName) + ".tbl",
+				FileName = $"{Path.GetFileNameWithoutExtension(romName)}.tbl",
 				InitialDirectory = intialDirectory,
 				Filter = "Text Table files (*.tbl)|*.tbl|All Files|*.*",
 				RestoreDirectory = false

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Client.cs

@@ -320,7 +320,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				Global.Config.TargetZoomFactors[Emulator.SystemId] = size;
 				GlobalWin.MainForm.FrameBufferResized();
-				GlobalWin.OSD.AddMessage("Window size set to " + size + "x");
+				GlobalWin.OSD.AddMessage($"Window size set to {size}x");
 			}
 			else
 			{

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Communication.cs

@@ -55,7 +55,7 @@ namespace BizHawk.Client.EmuHawk
 		[LuaMethod("socketServerSend", "sends a string to the Socket server")]
 		public string SocketServerSend(string SendString)
 		{
-			return "Sent : " + GlobalWin.socketServer.SendString(SendString).ToString() + " bytes";
+			return $"Sent : {GlobalWin.socketServer.SendString(SendString)} bytes";
 		}
 		[LuaMethod("socketServerResponse", "receives a message from the Socket server")]
 		public string SocketServerResponse()

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Console.cs

@@ -87,7 +87,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (outputs == null)
 			{
-				GlobalWin.Tools.LuaConsole.WriteToOutputWindow("(no return)" + terminator);
+				GlobalWin.Tools.LuaConsole.WriteToOutputWindow($"(no return){terminator}");
 				return;
 			}
 

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Forms.cs

@@ -754,7 +754,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				ConsoleLuaLibrary.Log("File not found: " + path + "\nScript Terminated");
+				ConsoleLuaLibrary.Log($"File not found: {path}\nScript Terminated");
 				return;
 			}
 			try
@@ -823,7 +823,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				ConsoleLuaLibrary.Log("File not found: " + path + "\nScript Terminated");
+				ConsoleLuaLibrary.Log($"File not found: {path}\nScript Terminated");
 				return;
 			}
 			try

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Gui.cs

@@ -323,7 +323,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				Log("File not found: " + path);
+				Log($"File not found: {path}");
 				return;
 			}
 
@@ -365,7 +365,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				Log("File not found: " + path);
+				Log($"File not found: {path}");
 				return;
 			}
 

BizHawk.Client.EmuHawk/tools/Lua/Libraries/EmuLuaLibrary.Savestate.cs

@@ -37,7 +37,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (slotNum >= 0 && slotNum <= 9)
 			{
-				GlobalWin.MainForm.LoadQuickSave("QuickSave" + slotNum, true);
+				GlobalWin.MainForm.LoadQuickSave($"QuickSave{slotNum}", true);
 			}
 		}
 
@@ -54,7 +54,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (slotNum >= 0 && slotNum <= 9)
 			{
-				GlobalWin.MainForm.SaveQuickSave("QuickSave" + slotNum);
+				GlobalWin.MainForm.SaveQuickSave($"QuickSave{slotNum}");
 			}
 		}
 	}

BizHawk.Client.EmuHawk/tools/Lua/LuaCanvas.cs

@@ -186,7 +186,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				ConsoleLuaLibrary.Log("File not found: " + path + "\nScript Terminated");
+				ConsoleLuaLibrary.Log($"File not found: {path}\nScript Terminated");
 				return;
 			}
 
@@ -212,7 +212,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (!File.Exists(path))
 			{
-				ConsoleLuaLibrary.Log("File not found: " + path + "\nScript Terminated");
+				ConsoleLuaLibrary.Log($"File not found: {path}\nScript Terminated");
 				return;
 			}
 

BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs

@@ -194,7 +194,7 @@ namespace BizHawk.Client.EmuHawk
 				LuaImp.ScriptList.AddRange(currentScripts);
 			}
 
-			InputBox.AutoCompleteCustomSource.AddRange(LuaImp.Docs.Select(a => a.Library + "." + a.Name).ToArray());
+			InputBox.AutoCompleteCustomSource.AddRange(LuaImp.Docs.Select(a => $"{a.Library}.{a.Name}").ToArray());
 
 			foreach (var file in runningScripts)
 			{
@@ -254,7 +254,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void OnChanged(object source, FileSystemEventArgs e)
 		{
-			string message = "File: " + e.FullPath + " " + e.ChangeType;
+			string message = $"File: {e.FullPath} {e.ChangeType}";
 			Invoke(new MethodInvoker(delegate
 			{
 				RefreshScriptMenuItem_Click(null, null);
@@ -451,15 +451,15 @@ namespace BizHawk.Client.EmuHawk
 
 			if (total == 1)
 			{
-				message += total + " script (" + active + " active, " + paused + " paused)";
+				message += $"{total} script ({active} active, {paused} paused)";
 			}
 			else if (total == 0)
 			{
-				message += total + " scripts";
+				message += $"{total} scripts";
 			}
 			else
 			{
-				message += total + " scripts (" + active + " active, " + paused + " paused)";
+				message += $"{total} scripts ({active} active, {paused} paused)";
 			}
 
 			NumberOfScripts.Text = message;
@@ -636,7 +636,7 @@ namespace BizHawk.Client.EmuHawk
 			if (file != null)
 			{
 				LuaImp.ScriptList.SaveSession(file.FullName);
-				OutputMessages.Text = Path.GetFileName(LuaImp.ScriptList.Filename) + " saved.";
+				OutputMessages.Text = $"{Path.GetFileName(LuaImp.ScriptList.Filename)} saved.";
 			}
 		}
 
@@ -769,7 +769,7 @@ namespace BizHawk.Client.EmuHawk
 					SaveSessionAs();
 				}
 
-				OutputMessages.Text = Path.GetFileName(LuaImp.ScriptList.Filename) + " saved.";
+				OutputMessages.Text = $"{Path.GetFileName(LuaImp.ScriptList.Filename)} saved.";
 			}
 		}
 
@@ -911,7 +911,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 			catch (IOException)
 			{
-				ConsoleLog("Unable to access file " + item.Path);
+				ConsoleLog($"Unable to access file {item.Path}");
 			}
 			catch (Exception ex)
 			{
@@ -973,7 +973,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					InitialDirectory = Path.GetDirectoryName(script.Path),
 					DefaultExt = ".lua",
-					FileName = Path.GetFileNameWithoutExtension(script.Path) + " (1)",
+					FileName = $"{Path.GetFileNameWithoutExtension(script.Path)} (1)",
 					OverwritePrompt = true,
 					Filter = "Lua Scripts (*.lua)|*.lua|All Files (*.*)|*.*"
 				};

BizHawk.Client.EmuHawk/tools/Lua/LuaFunctionsForm.cs

@@ -23,7 +23,7 @@ namespace BizHawk.Client.EmuHawk
 			if (!string.IsNullOrWhiteSpace(FilterBox.Text))
 			{
 				_filteredList = FunctionList
-					.Where(f => (f.Library + "." + f.Name).ToLowerInvariant().Contains(FilterBox.Text.ToLowerInvariant()))
+					.Where(f => $"{f.Library}.{f.Name}".ToLowerInvariant().Contains(FilterBox.Text.ToLowerInvariant()))
 					.ToList();
 			}
 			else

BizHawk.Client.EmuHawk/tools/Macros/MacroInput.ButtonSelect.cs

@@ -59,7 +59,7 @@ namespace BizHawk.Client.EmuHawk
 			for (int i = 0; i < _buttonBoxes.Length; i++)
 			{
 				if (!_buttonBoxes[i].Checked)
-					key = key.Replace(_buttonBoxes[i].Text + "|", "");
+					key = key.Replace($"{_buttonBoxes[i].Text}|", "");
 			}
 			key = key.Substring(0, key.Length - 1);
 

BizHawk.Client.EmuHawk/tools/Macros/MacroInput.cs

@@ -57,7 +57,7 @@ namespace BizHawk.Client.EmuHawk
 			};
 
 			_zones.Add(main);
-			ZonesList.Items.Add(main.Name + " - length: " + main.Length);
+			ZonesList.Items.Add($"{main.Name} - length: {main.Length}");
 			ZonesList.Items[0] += " [Zones don't change!]";
 
 			SetUpButtonBoxes();
@@ -150,9 +150,9 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			var newZone = new MovieZone(CurrentMovie, (int)StartNum.Value, (int)(EndNum.Value - StartNum.Value + 1));
-			newZone.Name = "Zone " + _zones.Count;
+			newZone.Name = $"Zone {_zones.Count}";
 			_zones.Add(newZone);
-			ZonesList.Items.Add(newZone.Name + " - length: " + newZone.Length);
+			ZonesList.Items.Add($"{newZone.Name} - length: {newZone.Length}");
 
 			_unsavedZones.Add(ZonesList.Items.Count - 1);
 		}
@@ -193,7 +193,7 @@ namespace BizHawk.Client.EmuHawk
 			}
 
 			selectedZone.Name = NameTextbox.Text;
-			ZonesList.Items[ZonesList.SelectedIndex] = selectedZone.Name + " - length: " + selectedZone.Length;
+			ZonesList.Items[ZonesList.SelectedIndex] = $"{selectedZone.Name} - length: {selectedZone.Length}";
 		}
 
 		private void PlaceNum_ValueChanged(object sender, EventArgs e)
@@ -266,7 +266,7 @@ namespace BizHawk.Client.EmuHawk
 			if (loadZone != null)
 			{
 				_zones.Add(loadZone);
-				ZonesList.Items.Add(loadZone.Name + " - length: " + loadZone.Length);
+				ZonesList.Items.Add($"{loadZone.Name} - length: {loadZone.Length}");
 
 				// Options only for TasMovie
 				if (!(CurrentMovie is TasMovie))
@@ -288,7 +288,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			MovieZone loadZone = new MovieZone(path);
 			_zones.Add(loadZone);
-			ZonesList.Items.Add(loadZone.Name + " - length: " + loadZone.Length);
+			ZonesList.Items.Add($"{loadZone.Name} - length: {loadZone.Length}");
 		}
 
 		private static string SuggestedFolder()

BizHawk.Client.EmuHawk/tools/Macros/MovieZone.cs

@@ -129,7 +129,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (movie is TasMovie)
 			{
-				(movie as TasMovie).ChangeLog.BeginNewBatch("Place Macro at " + Start);
+				(movie as TasMovie).ChangeLog.BeginNewBatch($"Place Macro at {Start}");
 			}
 
 			if (Start > movie.InputLogLength)
@@ -203,7 +203,7 @@ namespace BizHawk.Client.EmuHawk
 			header[0] = InputKey;
 			header[1] = Global.Emulator.ControllerDefinition.Name;
 			header[2] = Global.Emulator.ControllerDefinition.PlayerCount.ToString();
-			header[3] = Overlay.ToString() + "," + Replace.ToString();
+			header[3] = $"{Overlay},{Replace}";
 
 			File.WriteAllLines(fileName, header);
 			File.AppendAllLines(fileName, _log);
@@ -232,8 +232,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				if (!emuKeys.Contains(macroKeys[i]))
 				{
-					System.Windows.Forms.MessageBox.Show("The selected macro is not compatible with the current emulator core." +
+					System.Windows.Forms.MessageBox.Show($"The selected macro is not compatible with the current emulator core.\nMacro controller: {readText[1]}\nMacro player count: {readText[2]}", "Error");
-						"\nMacro controller: " + readText[1] + "\nMacro player count: " + readText[2], "Error");
 					return;
 				}
 			}

BizHawk.Client.EmuHawk/tools/MultiDiskBundler/MultiDiskFileSelector.cs

@@ -114,7 +114,7 @@ namespace BizHawk.Client.EmuHawk
                             }
 
                             var intName = hf.ArchiveItems[memIdx];
-                            PathBox.Text = _path + "|" + intName.Name;
+                            PathBox.Text = $"{_path}|{intName.Name}";
                         }
                         else
                         {

BizHawk.Client.EmuHawk/tools/NES/BarcodeEntry.cs

@@ -57,7 +57,7 @@ namespace BizHawk.Client.EmuHawk
 			string why;
 			if (!DatachBarcode.ValidString(textBox1.Text, out why))
 			{
-				label3.Text = "Invalid: " + why;
+				label3.Text = $"Invalid: {why}";
 				label3.Visible = true;
 				button1.Enabled = false;
 			}

BizHawk.Client.EmuHawk/tools/NES/NESMusicRipper.cs

@@ -59,7 +59,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			int tone = note % 12;
 			int octave = note / 12;
-			return string.Format("{0}{1}", noteNames[tone], octave);
+			return $"{noteNames[tone]}{octave}";
 		}
 
 		//this isnt thoroughly debugged but it seems to work OK
@@ -471,7 +471,7 @@ namespace BizHawk.Client.EmuHawk
 
 		void SyncContents()
 		{
-			lblContents.Text = string.Format("{0} Rows", Log.Count);
+			lblContents.Text = $"{Log.Count} Rows";
 		}
 
 		private void btnControl_Click(object sender, EventArgs e)

BizHawk.Client.EmuHawk/tools/NES/NESNameTableViewer.cs

@@ -312,11 +312,11 @@ namespace BizHawk.Client.EmuHawk
 				TileY = e.Y / 16;
 			}
 
-			XYLabel.Text = TileX + " : " + TileY;
+			XYLabel.Text = $"{TileX} : {TileY}";
 			int PPUAddress = 0x2000 + (NameTable * 0x400) + ((TileY % 30) * 32) + (TileX % 32);
-			PPUAddressLabel.Text = string.Format("{0:X4}", PPUAddress);
+			PPUAddressLabel.Text = $"{PPUAddress:X4}";
 			int TileID = _ppu.PeekPPU(PPUAddress);
-			TileIDLabel.Text = string.Format("{0:X2}", TileID);
+			TileIDLabel.Text = $"{TileID:X2}";
 			TableLabel.Text = NameTable.ToString();
 
 			int ytable = 0, yline = 0;

BizHawk.Client.EmuHawk/tools/NES/NESPPU.cs

@@ -294,8 +294,8 @@ namespace BizHawk.Client.EmuHawk
 		private void UpdatePaletteSelection()
 		{
 			_forceChange = true;
-			Table0PaletteLabel.Text = "Palette: " + PatternView.Pal0;
+			Table0PaletteLabel.Text = $"Palette: {PatternView.Pal0}";
-			Table1PaletteLabel.Text = "Palette: " + PatternView.Pal1;
+			Table1PaletteLabel.Text = $"Palette: {PatternView.Pal1}";
 		}
 
 		private static Bitmap Section(Image srcBitmap, Rectangle section, bool is8x16)
@@ -532,7 +532,7 @@ namespace BizHawk.Client.EmuHawk
 						return;
 					}
 
-					toolStripStatusLabel1.Text = found.Text + " copied to clipboard.";
+					toolStripStatusLabel1.Text = $"{found.Text} copied to clipboard.";
 
 					Messagetimer.Stop();
 					Messagetimer.Start();
@@ -619,11 +619,11 @@ namespace BizHawk.Client.EmuHawk
 				tile &= ~1;
 			}
 
-			AddressLabel.Text = "Number: " + string.Format("{0:X2}", spriteNumber);
+			AddressLabel.Text = $"Number: {spriteNumber:X2}";
-			ValueLabel.Text = "X: " + string.Format("{0:X2}", x);
+			ValueLabel.Text = $"X: {x:X2}";
-			Value2Label.Text = "Y: " + string.Format("{0:X2}", y);
+			Value2Label.Text = $"Y: {y:X2}";
-			Value3Label.Text = "Tile: " + string.Format("{0:X2}", tile);
+			Value3Label.Text = $"Tile: {tile:X2}";
-			Value4Label.Text = "Color: " + color;
+			Value4Label.Text = $"Color: {color}";
 			Value5Label.Text = flags;
 
 			if (is8x16)
@@ -668,7 +668,7 @@ namespace BizHawk.Client.EmuHawk
 
 			int column = e.X / 16;
 			int addr = column + baseAddr;
-			AddressLabel.Text = "Address: 0x" + string.Format("{0:X4}", addr);
+			AddressLabel.Text = $"Address: 0x{addr:X4}";
 			int val;
 
 			var bmp = new Bitmap(64, 64);
@@ -679,20 +679,20 @@ namespace BizHawk.Client.EmuHawk
 			if (baseAddr == 0x3F00)
 			{
 				val = PALRAM[PaletteView.BgPalettes[column].Address];
-				ValueLabel.Text = "ID: BG" + (column / 4);
+				ValueLabel.Text = $"ID: BG{column / 4}";
 				g.FillRectangle(new SolidBrush(PaletteView.BgPalettes[column].Color), 0, 0, 64, 64);
 			}
 			else
 			{
 				val = PALRAM[PaletteView.SpritePalettes[column].Address];
-				ValueLabel.Text = "ID: SPR" + (column / 4);
+				ValueLabel.Text = $"ID: SPR{column / 4}";
 				g.FillRectangle(new SolidBrush(PaletteView.SpritePalettes[column].Color), 0, 0, 64, 64);
 			}
 
 			g.Dispose();
 
-			Value3Label.Text = "Color: 0x" + string.Format("{0:X2}", val);
+			Value3Label.Text = $"Color: 0x{val:X2}";
-			Value4Label.Text = "Offset: " + (addr & 0x03);
+			Value4Label.Text = $"Offset: {addr & 0x03}";
 			ZoomBox.Image = bmp;
 		}
 
@@ -772,9 +772,9 @@ namespace BizHawk.Client.EmuHawk
 				usage += " (SPR16)";
 			}
 
-			AddressLabel.Text = "Address: " + string.Format("{0:X4}", address);
+			AddressLabel.Text = $"Address: {address:X4}";
-			ValueLabel.Text = "Table " + table;
+			ValueLabel.Text = $"Table {table}";
-			Value3Label.Text = "Tile " + string.Format("{0:X2}", tile);
+			Value3Label.Text = $"Tile {tile:X2}";
 			Value4Label.Text = usage;
 
 			ZoomBox.Image = Section(PatternView.pattern, new Rectangle(new Point((e.X / 8) * 8, (e.Y / 8) * 8), new Size(8, 8)), false);

BizHawk.Client.EmuHawk/tools/NES/NameTableViewer.cs

@@ -71,7 +71,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var sfd = new SaveFileDialog
 				{
-					FileName = PathManager.FilesystemSafeName(Global.Game) + "-Nametables",
+					FileName = $"{PathManager.FilesystemSafeName(Global.Game)}-Nametables",
 					InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries["NES", "Screenshots"].Path, "NES"),
 					Filter = "PNG (*.png)|*.png|Bitmap (*.bmp)|*.bmp|All Files|*.*",
 					RestoreDirectory = true

BizHawk.Client.EmuHawk/tools/NES/PaletteViewer.cs

@@ -78,7 +78,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var sfd = new SaveFileDialog
 				{
-					FileName = PathManager.FilesystemSafeName(Global.Game) + "-Palettes",
+					FileName = $"{PathManager.FilesystemSafeName(Global.Game)}-Palettes",
 					InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries["NES", "Screenshots"].Path, "NES"),
 					Filter = "PNG (*.png)|*.png|Bitmap (*.bmp)|*.bmp|All Files|*.*",
 					RestoreDirectory = true

BizHawk.Client.EmuHawk/tools/NES/PatternViewer.cs

@@ -39,7 +39,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var sfd = new SaveFileDialog
 				{
-					FileName = PathManager.FilesystemSafeName(Global.Game) + "-Patterns",
+					FileName = $"{PathManager.FilesystemSafeName(Global.Game)}-Patterns",
 					InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries["NES", "Screenshots"].Path, "NES"),
 					Filter = "PNG (*.png)|*.png|Bitmap (*.bmp)|*.bmp|All Files|*.*",
 					RestoreDirectory = true

BizHawk.Client.EmuHawk/tools/NES/SpriteViewer.cs

@@ -44,7 +44,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			var sfd = new SaveFileDialog
 				{
-					FileName = PathManager.FilesystemSafeName(Global.Game) + "-Sprites",
+					FileName = $"{PathManager.FilesystemSafeName(Global.Game)}-Sprites",
 					InitialDirectory = PathManager.MakeAbsolutePath(Global.Config.PathEntries["NES", "Screenshots"].Path, "NES"),
 					Filter = "PNG (*.png)|*.png|Bitmap (*.bmp)|*.bmp|All Files|*.*",
 					RestoreDirectory = true

BizHawk.Client.EmuHawk/tools/PCE/PCEBGViewer.cs

@@ -145,7 +145,7 @@ namespace BizHawk.Client.EmuHawk
 			int tileNo = vdc.VRAM[(ushort)((yTile * vdc.BatWidth) + xTile)] & 0x07FF;
 			int paletteNo = vdc.VRAM[(ushort)((yTile * vdc.BatWidth) + xTile)] >> 12;
 			TileIDLabel.Text = tileNo.ToString();
-			XYLabel.Text = xTile + ":" + yTile;
+			XYLabel.Text = $"{xTile}:{yTile}";
 			PaletteLabel.Text = paletteNo.ToString();
 		}
 

BizHawk.Client.EmuHawk/tools/PCE/PCESoundDebugger.cs

@@ -190,7 +190,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void btnExport_Click(object sender, EventArgs e)
 		{
-			string tmpf = Path.GetTempFileName() + ".zip";
+			string tmpf = $"{Path.GetTempFileName()}.zip";
 			using (var stream = new FileStream(tmpf, FileMode.Create, FileAccess.Write, FileShare.Read))
 			{
 				var zip = new ZipOutputStream(stream)
@@ -201,7 +201,7 @@ namespace BizHawk.Client.EmuHawk
 
 				foreach (var entry in PSGEntries)
 				{
-					var ze = new ZipEntry(entry.name + ".wav") { CompressionMethod = CompressionMethod.Deflated };
+					var ze = new ZipEntry($"{entry.name}.wav") { CompressionMethod = CompressionMethod.Deflated };
 					zip.PutNextEntry(ze);
 					var ms = new MemoryStream();
 					var bw = new BinaryWriter(ms);

BizHawk.Client.EmuHawk/tools/SNES/SNESGameGenie.cs

@@ -318,8 +318,8 @@ namespace BizHawk.Client.EmuHawk
 				{
 					int val = 0, add = 0;
 					SnesGGDecode(GGCodeMaskBox.Text, ref val, ref add);
-					AddressBox.Text = string.Format("{0:X6}", add);
+					AddressBox.Text = $"{add:X6}";
-					ValueBox.Text = string.Format("{0:X2}", val);
+					ValueBox.Text = $"{val:X2}";
 					addcheatbt.Enabled = true;
 				}
 				else

BizHawk.Client.EmuHawk/tools/SNES/SNESGraphicsDebugger.cs

@@ -130,8 +130,8 @@ namespace BizHawk.Client.EmuHawk
 		string FormatVramAddress(int address)
 		{
 			int excess = address & 1023;
-			if (excess != 0) return "@" + address.ToHexString(4);
+			if (excess != 0) return $"@{address.ToHexString(4)}";
-			else return string.Format("@{0} ({1}K)", address.ToHexString(4), address / 1024);
+			else return $"@{address.ToHexString(4)} ({address / 1024}K)";
 		}
 
 		public void NewUpdate(ToolFormUpdateType type) { }
@@ -245,7 +245,7 @@ namespace BizHawk.Client.EmuHawk
 				txtOBSELSizeBits.Text = si.OBSEL_Size.ToString();
 				txtOBSELBaseBits.Text = si.OBSEL_NameBase.ToString();
 				txtOBSELT1OfsBits.Text = si.OBSEL_NameSel.ToString();
-				txtOBSELSizeDescr.Text = string.Format("{0}, {1}", SNESGraphicsDecoder.ObjSizes[si.OBSEL_Size, 0], SNESGraphicsDecoder.ObjSizes[si.OBSEL_Size, 1]);
+				txtOBSELSizeDescr.Text = $"{SNESGraphicsDecoder.ObjSizes[si.OBSEL_Size, 0]}, {SNESGraphicsDecoder.ObjSizes[si.OBSEL_Size, 1]}";
 				txtOBSELBaseDescr.Text = FormatVramAddress(si.OBJTable0Addr);
 				txtOBSELT1OfsDescr.Text = FormatVramAddress(si.OBJTable1Addr);
 
@@ -282,7 +282,7 @@ namespace BizHawk.Client.EmuHawk
 				txtBG1SizeBits.Text = bg.SCSIZE.ToString();
 				txtBG1SizeInTiles.Text = bg.ScreenSizeInTiles.ToString();
 				int size = bg.ScreenSizeInTiles.Width * bg.ScreenSizeInTiles.Height * 2 / 1024;
-				txtBG1MapSizeBytes.Text = string.Format("({0}K)", size);
+				txtBG1MapSizeBytes.Text = $"({size}K)";
 				txtBG1SCAddrBits.Text = bg.SCADDR.ToString();
 				txtBG1SCAddrDescr.Text = FormatVramAddress(bg.ScreenAddr);
 				txtBG1Colors.Text = (1 << bg.Bpp).ToString();
@@ -290,17 +290,17 @@ namespace BizHawk.Client.EmuHawk
 				txtBG1TDAddrBits.Text = bg.TDADDR.ToString();
 				txtBG1TDAddrDescr.Text = FormatVramAddress(bg.TiledataAddr);
 
-				txtBG1Scroll.Text = string.Format("({0},{1})", bg.HOFS, bg.VOFS);
+				txtBG1Scroll.Text = $"({bg.HOFS},{bg.VOFS})";
 
 				if (bg.Bpp != 0)
 				{
 					var pi = bg.PaletteSelection;
-					txtBGPaletteInfo.Text = string.Format("{0} colors from ${1:X2} - ${2:X2}", pi.size, pi.start, pi.start + pi.size - 1);
+					txtBGPaletteInfo.Text = $"{pi.size} colors from ${pi.start:X2} - ${pi.start + pi.size - 1:X2}";
 				}
 				else txtBGPaletteInfo.Text = "";
 
 				var sizeInPixels = bg.ScreenSizeInPixels;
-				txtBG1SizeInPixels.Text = string.Format("{0}x{1}", sizeInPixels.Width, sizeInPixels.Height);
+				txtBG1SizeInPixels.Text = $"{sizeInPixels.Width}x{sizeInPixels.Height}";
 
 				checkTMOBJ.Checked = si.OBJ_MainEnabled;
 				checkTMBG1.Checked = si.BG.BG1.MainEnabled;
@@ -724,7 +724,7 @@ namespace BizHawk.Client.EmuHawk
 		static string BGModeShortName(SNESGraphicsDecoder.BGMode mode, int bpp)
 		{
 			if (mode == SNESGraphicsDecoder.BGMode.Unavailable) return "Unavailable";
-			if (mode == SNESGraphicsDecoder.BGMode.Text) return string.Format("Text{0}bpp", bpp);
+			if (mode == SNESGraphicsDecoder.BGMode.Text) return $"Text{bpp}bpp";
 			if (mode == SNESGraphicsDecoder.BGMode.OBJ) return string.Format("OBJ", bpp);
 			if (mode == SNESGraphicsDecoder.BGMode.Mode7) return "Mode7";
 			if (mode == SNESGraphicsDecoder.BGMode.Mode7Ext) return "Mode7Ext";
@@ -736,17 +736,17 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (currObjDataState == null) return;
 			var oam = new SNESGraphicsDecoder.OAMInfo(gd, si, currObjDataState.Number);
-			txtObjNumber.Text = string.Format("#${0:X2}", currObjDataState.Number);
+			txtObjNumber.Text = $"#${currObjDataState.Number:X2}";
-			txtObjCoord.Text = string.Format("({0}, {1})",oam.X,oam.Y);
+			txtObjCoord.Text = $"({oam.X}, {oam.Y})";
 			cbObjHFlip.Checked = oam.HFlip;
 			cbObjVFlip.Checked = oam.VFlip;
 			cbObjLarge.Checked = oam.Size == 1;
 			txtObjSize.Text = SNESGraphicsDecoder.ObjSizes[si.OBSEL_Size, oam.Size].ToString();
 			txtObjPriority.Text = oam.Priority.ToString();
 			txtObjPalette.Text = oam.Palette.ToString();
-			txtObjPaletteMemo.Text = string.Format("${0:X2}", oam.Palette * 16 + 128);
+			txtObjPaletteMemo.Text = $"${oam.Palette * 16 + 128:X2}";
-			txtObjName.Text = string.Format("#${0:X3}", oam.Tile);
+			txtObjName.Text = $"#${oam.Tile:X3}";
-			txtObjNameAddr.Text = string.Format("@{0:X4}", oam.Address);
+			txtObjNameAddr.Text = $"@{oam.Address:X4}";
 		}
 
 		void UpdateTileDetails()
@@ -757,18 +757,18 @@ namespace BizHawk.Client.EmuHawk
 			txtTileMode.Text = BGModeShortName(mode, bpp);
 			txtTileBpp.Text = currTileDataState.Bpp.ToString();
 			txtTileColors.Text = (1 << currTileDataState.Bpp).ToString();
-			txtTileNumber.Text = string.Format("#${0:X3}", currTileDataState.Tile);
+			txtTileNumber.Text = $"#${currTileDataState.Tile:X3}";
-			txtTileAddress.Text = string.Format("@{0:X4}", currTileDataState.Address);
+			txtTileAddress.Text = $"@{currTileDataState.Address:X4}";
-			txtTilePalette.Text = string.Format("#{0:X2}", currTileDataState.Palette);
+			txtTilePalette.Text = $"#{currTileDataState.Palette:X2}";
 		}
 
 		void UpdateMapEntryDetails()
 		{
 			if (currMapEntryState == null) return;
-			txtMapEntryLocation.Text = string.Format("({0},{1}), @{2:X4}", currMapEntryState.Location.X, currMapEntryState.Location.Y, currMapEntryState.entry.address);
+			txtMapEntryLocation.Text = $"({currMapEntryState.Location.X},{currMapEntryState.Location.Y}), @{currMapEntryState.entry.address:X4}";
-			txtMapEntryTileNum.Text = string.Format("${0:X3}", currMapEntryState.entry.tilenum);
+			txtMapEntryTileNum.Text = $"${currMapEntryState.entry.tilenum:X3}";
-			txtMapEntryPrio.Text = string.Format("{0}", (currMapEntryState.entry.flags & SNESGraphicsDecoder.TileEntryFlags.Priority)!=0?1:0);
+			txtMapEntryPrio.Text = $"{((currMapEntryState.entry.flags & SNESGraphicsDecoder.TileEntryFlags.Priority) != 0 ? 1 : 0)}";
-			txtMapEntryPalette.Text = string.Format("{0}", currMapEntryState.entry.palette);
+			txtMapEntryPalette.Text = $"{currMapEntryState.entry.palette}";
 			checkMapEntryHFlip.Checked = (currMapEntryState.entry.flags & SNESGraphicsDecoder.TileEntryFlags.Horz) != 0;
 			checkMapEntryVFlip.Checked = (currMapEntryState.entry.flags & SNESGraphicsDecoder.TileEntryFlags.Vert) != 0;
 
@@ -786,7 +786,7 @@ namespace BizHawk.Client.EmuHawk
 				addr *= 2;
 
 			addr &= 0xFFFF;
-			txtMapEntryTileAddr.Text = "@" + addr.ToHexString(4);
+			txtMapEntryTileAddr.Text = $"@{addr.ToHexString(4)}";
 		}
 
 		void UpdateColorDetails()
@@ -798,19 +798,19 @@ namespace BizHawk.Client.EmuHawk
 			int color = gd.Colorize(rgb555);
 			pnDetailsPaletteColor.BackColor = Color.FromArgb(color);
 
-			txtDetailsPaletteColor.Text = string.Format("${0:X4}", rgb555);
+			txtDetailsPaletteColor.Text = $"${rgb555:X4}";
-			txtDetailsPaletteColorHex.Text = string.Format("#{0:X6}", color & 0xFFFFFF);
+			txtDetailsPaletteColorHex.Text = $"#{color & 0xFFFFFF:X6}";
-			txtDetailsPaletteColorRGB.Text = string.Format("({0},{1},{2})", (color >> 16) & 0xFF, (color >> 8) & 0xFF, (color & 0xFF));
+			txtDetailsPaletteColorRGB.Text = $"({(color >> 16) & 0xFF},{(color >> 8) & 0xFF},{(color & 0xFF)})";
 
-			txtPaletteDetailsIndexHex.Text = string.Format("${0:X2}", lastColorNum);
+			txtPaletteDetailsIndexHex.Text = $"${lastColorNum:X2}";
-			txtPaletteDetailsIndex.Text = string.Format("{0}", lastColorNum);
+			txtPaletteDetailsIndex.Text = $"{lastColorNum}";
 
 			//not being used anymore
 			//if (lastColorNum < 128) lblDetailsOBJOrBG.Text = "(BG:)"; else lblDetailsOBJOrBG.Text = "(OBJ:)";
-			//txtPaletteDetailsIndexHexSpecific.Text = string.Format("${0:X2}", lastColorNum & 0x7F);
+			//txtPaletteDetailsIndexHexSpecific.Text = $"${lastColorNum & 0x7F:X2}";
-			//txtPaletteDetailsIndexSpecific.Text = string.Format("{0}", lastColorNum & 0x7F);
+			//txtPaletteDetailsIndexSpecific.Text = $"{lastColorNum & 0x7F}";
 
-			txtPaletteDetailsAddress.Text = string.Format("${0:X3}", lastColorNum * 2);
+			txtPaletteDetailsAddress.Text = $"${lastColorNum * 2:X3}";
 		}
 
 
@@ -1313,7 +1313,7 @@ namespace BizHawk.Client.EmuHawk
 						label = "Map Entry";
 					if (found.Name == "paletteViewer")
 						label = "Palette";
-					labelClipboard.Text = label + " copied to clipboard.";
+					labelClipboard.Text = $"{label} copied to clipboard.";
 					messagetimer.Stop();
 					messagetimer.Start();
 

BizHawk.Client.EmuHawk/tools/TAStudio/BookmarksBranchesBox.cs

@@ -226,7 +226,7 @@ namespace BizHawk.Client.EmuHawk
 				Movie.CurrentBranch = index;
 				LoadBranch(SelectedBranch);
 				BranchView.Refresh();
-				GlobalWin.OSD.AddMessage("Loaded branch " + Movie.CurrentBranch.ToString());
+				GlobalWin.OSD.AddMessage($"Loaded branch {Movie.CurrentBranch}");
 			}
 		}
 
@@ -244,7 +244,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			Branch();
 			CallSavedCallback(Movie.BranchCount - 1);
-			GlobalWin.OSD.AddMessage("Added branch " + Movie.CurrentBranch.ToString());
+			GlobalWin.OSD.AddMessage($"Added branch {Movie.CurrentBranch}");
 		}
 
 		private void AddBranchWithTexToolStripMenuItem_Click(object sender, EventArgs e)
@@ -252,7 +252,7 @@ namespace BizHawk.Client.EmuHawk
 			Branch();
 			EditBranchTextPopUp(Movie.CurrentBranch);
 			CallSavedCallback(Movie.BranchCount - 1);
-			GlobalWin.OSD.AddMessage("Added branch " + Movie.CurrentBranch.ToString());
+			GlobalWin.OSD.AddMessage($"Added branch {Movie.CurrentBranch}");
 		}
 
 		private void LoadBranchToolStripMenuItem_Click(object sender, EventArgs e)
@@ -292,7 +292,7 @@ namespace BizHawk.Client.EmuHawk
 
 				UpdateBranch(SelectedBranch);
 				CallSavedCallback(Movie.CurrentBranch);
-				GlobalWin.OSD.AddMessage("Saved branch " + Movie.CurrentBranch);
+				GlobalWin.OSD.AddMessage($"Saved branch {Movie.CurrentBranch}");
 			}
 		}
 
@@ -312,7 +312,7 @@ namespace BizHawk.Client.EmuHawk
 					toolTip1.SetToolTip(UndoBranchButton, "Undo Branch Text Edit");
 					_branchUndo = BranchUndo.Text;
 
-					GlobalWin.OSD.AddMessage("Edited branch " + index.ToString());
+					GlobalWin.OSD.AddMessage($"Edited branch {index}");
 				}
 			}
 		}
@@ -358,7 +358,7 @@ namespace BizHawk.Client.EmuHawk
 
 				CallRemovedCallback(index);
 				Tastudio.RefreshDialog();
-				GlobalWin.OSD.AddMessage("Removed branch " + index.ToString());
+				GlobalWin.OSD.AddMessage($"Removed branch {index}");
 			}
 		}
 
@@ -578,7 +578,7 @@ namespace BizHawk.Client.EmuHawk
 
 			var i = new InputPrompt
 			{
-				Text = "Text for branch " + index,
+				Text = $"Text for branch {index}",
 				TextInputType = InputPrompt.InputType.Text,
 				Message = "Enter a message",
 				InitialValue = branch.UserText

BizHawk.Client.EmuHawk/tools/TAStudio/GreenzoneSettings.cs

@@ -36,7 +36,7 @@ namespace BizHawk.Client.EmuHawk
 			MemStateGapDividerNumeric.Value = NumberExtensions.Clamp(_settings.MemStateGapDivider, MemStateGapDividerNumeric.Minimum, MemStateGapDividerNumeric.Maximum);
 
 			FileStateGapNumeric.Value = _settings.FileStateGap;
-			SavestateSizeLabel.Text = Math.Round(_stateSizeMb, 2).ToString() + " MB";
+			SavestateSizeLabel.Text = $"{Math.Round(_stateSizeMb, 2)} MB";
 			CapacityNumeric_ValueChanged(null, null);
 			SaveCapacityNumeric_ValueChanged(null, null);
 		}

BizHawk.Client.EmuHawk/tools/TAStudio/MarkerControl.cs

@@ -183,7 +183,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				var i = new InputPrompt
 				{
-					Text = "Marker for frame " + markerFrame,
+					Text = $"Marker for frame {markerFrame}",
 					TextInputType = InputPrompt.InputType.Text,
 					Message = "Enter a message",
 					InitialValue =
@@ -218,7 +218,7 @@ namespace BizHawk.Client.EmuHawk
 			var point = default(Point);
 			var i = new InputPrompt
 			{
-				Text = "Marker for frame " + markerFrame,
+				Text = $"Marker for frame {markerFrame}",
 				TextInputType = InputPrompt.InputType.Text,
 				Message = "Enter a message",
 				InitialValue =

BizHawk.Client.EmuHawk/tools/TAStudio/PatternsForm.cs

@@ -157,7 +157,7 @@ namespace BizHawk.Client.EmuHawk
 			int index = 0;
 			for (int i = 0; i < _counts.Count; i++)
 			{
-				string str = index + ": ";
+				string str = $"{index}: ";
 				if (IsBool)
 				{
 					str += _values[i][0] == 'T' ? "On" : "Off";
@@ -167,11 +167,11 @@ namespace BizHawk.Client.EmuHawk
 					str += _values[i];
 				}
 
-				PatternList.Items.Add(str + ("\t(x" + _counts[i] + ")"));
+				PatternList.Items.Add($"{str}\t(x{_counts[i]})");
 				index += _counts[i];
 			}
 
-			PatternList.Items.Add("Loop to: " + _loopAt);
+			PatternList.Items.Add($"Loop to: {_loopAt}");
 
 			if (oldIndex >= PatternList.Items.Count)
 			{

BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.ListView.cs

@@ -344,7 +344,7 @@ namespace BizHawk.Client.EmuHawk
 			catch (Exception ex)
 			{
 				text = "";
-				MessageBox.Show("oops\n" + ex);
+				MessageBox.Show($"oops\n{ex}");
 			}
 		}
 
@@ -643,7 +643,7 @@ namespace BizHawk.Client.EmuHawk
 						}
 						else
 						{
-							CurrentTasMovie.ChangeLog.BeginNewBatch("Paint Bool " + buttonName + " from frame " + frame);
+							CurrentTasMovie.ChangeLog.BeginNewBatch($"Paint Bool {buttonName} from frame {frame}");
 
 							CurrentTasMovie.ToggleBoolState(TasView.CurrentCell.RowIndex.Value, buttonName);
 							_boolPaintState = CurrentTasMovie.BoolIsPressed(frame, buttonName);
@@ -683,7 +683,7 @@ namespace BizHawk.Client.EmuHawk
 
 						if (e.Clicks != 2 && !Settings.SingleClickFloatEdit)
 						{
-							CurrentTasMovie.ChangeLog.BeginNewBatch("Paint Float " + buttonName + " from frame " + frame);
+							CurrentTasMovie.ChangeLog.BeginNewBatch($"Paint Float {buttonName} from frame {frame}");
 							_startFloatDrawColumn = buttonName;
 						}
 						else // Double-click enters float editing mode
@@ -694,7 +694,7 @@ namespace BizHawk.Client.EmuHawk
 							}
 							else
 							{
-								CurrentTasMovie.ChangeLog.BeginNewBatch("Float Edit: " + frame);
+								CurrentTasMovie.ChangeLog.BeginNewBatch($"Float Edit: {frame}");
 								_floatEditColumn = buttonName;
 								floatEditRow = frame;
 								_floatTypedValue = "";
@@ -1350,7 +1350,7 @@ namespace BizHawk.Client.EmuHawk
 				}
 				else
 				{
-					_floatTypedValue = "-" + _floatTypedValue;
+					_floatTypedValue = $"-{_floatTypedValue}";
 				}
 			}
 			else if (e.KeyCode == Keys.Back)