bump AnalysisModeGlobalization to Recommended

fixes CA1304, CA1309, CA1310, CA1311

temporarily silences CA1305

reduce severity of CA2101

.editorconfig

@@ -11,3 +11,7 @@ csharp_new_line_before_finally = true
 csharp_indent_switch_labels = true
 csharp_indent_case_contents = true
 csharp_indent_labels = one_less_than_current
+
+# Globalization rules
+dotnet_diagnostic.CA1305.severity = silent
+dotnet_diagnostic.CA2101.severity = suggestion

Common.props

@@ -1,6 +1,7 @@
 <Project>
 	<PropertyGroup>
 		<AnalysisLevel>6</AnalysisLevel>
+		<AnalysisModeGlobalization>Recommended</AnalysisModeGlobalization>
 		<CodeAnalysisRuleSet>$(MSBuildProjectDirectory)/../../Common.ruleset</CodeAnalysisRuleSet>
 		<ContinuousIntegrationBuild Condition=" '$(GITLAB_CI)' != '' Or '$(APPVEYOR)' != '' ">true</ContinuousIntegrationBuild>
 		<EnableNETAnalyzers>true</EnableNETAnalyzers>

ExternalProjects/BizHawk.SrcGen.ReflectionCache/ReflectionCacheGenerator.cs

@@ -48,7 +48,7 @@ namespace BizHawk.SrcGen.ReflectionCache
 				};
 				if (_namespace != null || syntaxNode is not NamespaceDeclarationSyntax syn) return;
 				var newNS = Ser(syn.Name);
-				if (!newNS.StartsWith("BizHawk.")) return;
+				if (!newNS.StartsWith("BizHawk.", StringComparison.Ordinal)) return;
 				_namespaces.Add(newNS);
 				if (_namespaces.Count == SAMPLE_SIZE) _namespace = CalcNamespace();
 			}
@@ -88,7 +88,7 @@ namespace {nSpace}
 		public static IEnumerable<string> EmbeddedResourceList(string extraPrefix)
 		{{
 			var fullPrefix = EMBED_PREFIX + extraPrefix;
-			return Asm.GetManifestResourceNames().Where(s => s.StartsWith(fullPrefix)).Select(s => s.RemovePrefix(fullPrefix));
+			return Asm.GetManifestResourceNames().Where(s => s.StartsWith(fullPrefix, StringComparison.Ordinal)).Select(s => s.RemovePrefix(fullPrefix));
 		}}
 
 		public static IEnumerable<string> EmbeddedResourceList()

src/BizHawk.Client.Common/Api/Classes/GuiApi.cs

@@ -160,17 +160,17 @@ namespace BizHawk.Client.Common
 		}
 
 		public readonly ref struct LuaAutoUnlockHack
-		{
-			private readonly GuiApi _guiApi;
-
-			internal LuaAutoUnlockHack(GuiApi guiApi)
-				=> _guiApi = guiApi;
-
-			public void Dispose()
-			{
-				_guiApi.UnlockSurface(DisplaySurfaceID.EmuCore);
-				_guiApi.UnlockSurface(DisplaySurfaceID.Client);
-			}
+		{
+			private readonly GuiApi _guiApi;
+
+			internal LuaAutoUnlockHack(GuiApi guiApi)
+				=> _guiApi = guiApi;
+
+			public void Dispose()
+			{
+				_guiApi.UnlockSurface(DisplaySurfaceID.EmuCore);
+				_guiApi.UnlockSurface(DisplaySurfaceID.Client);
+			}
 		}
 
 		public LuaAutoUnlockHack ThisIsTheLuaAutoUnlockHack()
@@ -491,7 +491,7 @@ namespace BizHawk.Client.Common
 			{
 				var family = fontfamily != null ? new FontFamily(fontfamily) : FontFamily.GenericMonospace;
 
-				var fstyle = fontstyle?.ToLower() switch
+				var fstyle = fontstyle?.ToLowerInvariant() switch
 				{
 					"bold" => FontStyle.Bold,
 					"italic" => FontStyle.Italic,
@@ -507,7 +507,7 @@ namespace BizHawk.Client.Common
 				var font = new Font(family, fontsize ?? 12, fstyle, GraphicsUnit.Pixel);
 				var sizeOfText = g.MeasureString(message, font, 0, new StringFormat(StringFormat.GenericDefault)).ToSize();
 
-				switch (horizalign?.ToLower())
+				switch (horizalign?.ToLowerInvariant())
 				{
 					default:
 					case "left":
@@ -521,7 +521,7 @@ namespace BizHawk.Client.Common
 						break;
 				}
 
-				switch (vertalign?.ToLower())
+				switch (vertalign?.ToLowerInvariant())
 				{
 					default:
 					case "top":
@@ -644,4 +644,4 @@ namespace BizHawk.Client.Common
 			foreach (var brush in _pens.Values) brush.Dispose();
 		}
 	}
-}
+}

src/BizHawk.Client.Common/Api/Classes/MovieApi.cs

@@ -98,7 +98,7 @@ namespace BizHawk.Client.Common
 
 		public int Length() => _movieSession.Movie.FrameCount;
 
-		public string Mode() => (_movieSession.Movie?.Mode ?? MovieMode.Inactive).ToString().ToUpper();
+		public string Mode() => (_movieSession.Movie?.Mode ?? MovieMode.Inactive).ToString().ToUpperInvariant();
 
 		public bool PlayFromStart(string path = "")
 		{

src/BizHawk.Client.Common/ArgParser.cs

@@ -7,6 +7,7 @@ using System.IO;
 using System.Net.Sockets;
 
 using BizHawk.Common.CollectionExtensions;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Client.Common
 {
@@ -59,28 +60,28 @@ namespace BizHawk.Client.Common
 					continue;
 				}
 
-				var argDowncased = arg.ToLower();
-				if (argDowncased.StartsWith("--load-slot="))
+				var argDowncased = arg.ToLowerInvariant();
+				if (argDowncased.StartsWithOrdinal("--load-slot="))
 				{
 					cmdLoadSlot = argDowncased.Substring(argDowncased.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--load-state="))
+				else if (argDowncased.StartsWithOrdinal("--load-state="))
 				{
 					cmdLoadState = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--config="))
+				else if (argDowncased.StartsWithOrdinal("--config="))
 				{
 					cmdConfigFile = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--movie="))
+				else if (argDowncased.StartsWithOrdinal("--movie="))
 				{
 					cmdMovie = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--dump-type="))
+				else if (argDowncased.StartsWithOrdinal("--dump-type="))
 				{
 					cmdDumpType = argDowncased.Substring(argDowncased.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--dump-frames="))
+				else if (argDowncased.StartsWithOrdinal("--dump-frames="))
 				{
 					string list = argDowncased.Substring(argDowncased.IndexOf('=') + 1);
 					string[] items = list.Split(',');
@@ -93,78 +94,78 @@ namespace BizHawk.Client.Common
 					// automatically set dump length to maximum frame
 					autoDumpLength = currAviWriterFrameList.Order().Last();
 				}
-				else if (argDowncased.StartsWith("--version"))
+				else if (argDowncased.StartsWithOrdinal("--version"))
 				{
 					printVersion = true;
 				}
-				else if (argDowncased.StartsWith("--dump-name="))
+				else if (argDowncased.StartsWithOrdinal("--dump-name="))
 				{
 					cmdDumpName = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--dump-length="))
+				else if (argDowncased.StartsWithOrdinal("--dump-length="))
 				{
 					var len = int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var i1) ? i1 : default;
 					autoDumpLength = len;
 				}
-				else if (argDowncased.StartsWith("--dump-close"))
+				else if (argDowncased.StartsWithOrdinal("--dump-close"))
 				{
 					autoCloseOnDump = true;
 				}
-				else if (argDowncased.StartsWith("--chromeless"))
+				else if (argDowncased.StartsWithOrdinal("--chromeless"))
 				{
 					// chrome is never shown, even in windowed mode
 					chromeless = true;
 				}
-				else if (argDowncased.StartsWith("--fullscreen"))
+				else if (argDowncased.StartsWithOrdinal("--fullscreen"))
 				{
 					startFullscreen = true;
 				}
-				else if (argDowncased.StartsWith("--lua="))
+				else if (argDowncased.StartsWithOrdinal("--lua="))
 				{
 					luaScript = arg.Substring(arg.IndexOf('=') + 1);
 					luaConsole = true;
 				}
-				else if (argDowncased.StartsWith("--luaconsole"))
+				else if (argDowncased.StartsWithOrdinal("--luaconsole"))
 				{
 					luaConsole = true;
 				}
-				else if (argDowncased.StartsWith("--socket_port="))
+				else if (argDowncased.StartsWithOrdinal("--socket_port="))
 				{
 					var port = int.TryParse(argDowncased.Substring(argDowncased.IndexOf('=') + 1), out var i1) ? i1 : default;
 					if (port > 0) socketPort = port;
 				}
-				else if (argDowncased.StartsWith("--socket_ip="))
+				else if (argDowncased.StartsWithOrdinal("--socket_ip="))
 				{
 					socketIP = argDowncased.Substring(argDowncased.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--socket_udp"))
+				else if (argDowncased.StartsWithOrdinal("--socket_udp"))
 				{
 					socketProtocol = ProtocolType.Udp;
 				}
-				else if (argDowncased.StartsWith("--mmf="))
+				else if (argDowncased.StartsWithOrdinal("--mmf="))
 				{
 					mmfFilename = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--url_get="))
+				else if (argDowncased.StartsWithOrdinal("--url_get="))
 				{
 					urlGet = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--url_post="))
+				else if (argDowncased.StartsWithOrdinal("--url_post="))
 				{
 					urlPost = arg.Substring(arg.IndexOf('=') + 1);
 				}
-				else if (argDowncased.StartsWith("--audiosync="))
+				else if (argDowncased.StartsWithOrdinal("--audiosync="))
 				{
 					audiosync = argDowncased.Substring(argDowncased.IndexOf('=') + 1) == "true";
 				}
-				else if (argDowncased.StartsWith("--open-ext-tool-dll="))
+				else if (argDowncased.StartsWithOrdinal("--open-ext-tool-dll="))
 				{
 					// the first ext. tool from ExternalToolManager.ToolStripMenu which satisfies both of these will be opened:
 					// - available (no load errors, correct system/rom, etc.)
 					// - dll path matches given string; or dll filename matches given string with or without `.dll`
 					openExtToolDll = arg.Substring(20);
 				}
-				else if (argDowncased.StartsWith("--userdata="))
+				else if (argDowncased.StartsWithOrdinal("--userdata="))
 				{
 					userdataUnparsedPairs = new();
 					foreach (var s in arg.Substring(11).Split(';'))

src/BizHawk.Client.Common/DisplayManager/Filters/Retro.cs

@@ -166,8 +166,7 @@ namespace BizHawk.Client.Common.Filters
 
 					value = value.Trim();
 				}
-
-				dict[key.ToLower()] = value;
+				dict[key.ToLowerInvariant()] = value;
 			}
 
 			// process the keys

src/BizHawk.Client.Common/RecentFiles.cs

@@ -71,7 +71,7 @@ namespace BizHawk.Client.Common
 		{
 			if (!Frozen)
 			{
-				return recentlist.RemoveAll(recent => string.Compare(newFile, recent, StringComparison.CurrentCultureIgnoreCase) == 0) != 0; // none removed => return false
+				return recentlist.RemoveAll(recent => string.Compare(newFile, recent, StringComparison.OrdinalIgnoreCase) == 0) != 0; // none removed => return false
 			}
 
 			return false;

src/BizHawk.Client.Common/RomGame.cs

@@ -65,7 +65,7 @@ namespace BizHawk.Client.Common
 
 				if (!string.IsNullOrWhiteSpace(GameInfo.Name) && GameInfo.Name == GameInfo.Name.ToUpperInvariant())
 				{
-					GameInfo.Name = Thread.CurrentThread.CurrentCulture.TextInfo.ToTitleCase(GameInfo.Name.ToLower());
+					GameInfo.Name = Thread.CurrentThread.CurrentCulture.TextInfo.ToTitleCase(GameInfo.Name.ToLowerInvariant());
 				}
 
 				return;

src/BizHawk.Client.Common/RomLoader.cs

@@ -389,7 +389,7 @@ namespace BizHawk.Client.Common
 							return (int)CorePriority.UserPreference;
 						}
 
-						if (string.Equals(c.Name, dbForcedCoreName, StringComparison.InvariantCultureIgnoreCase))
+						if (string.Equals(c.Name, dbForcedCoreName, StringComparison.OrdinalIgnoreCase))
 						{
 							return (int)CorePriority.GameDbPreference;
 						}

src/BizHawk.Client.Common/cheats/GameSharkDecoder.cs

@@ -1,4 +1,6 @@
-using BizHawk.Emulation.Common;
+using System;
+using BizHawk.Common.StringExtensions;
+using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.Common.cheats
 {
@@ -50,7 +52,7 @@ namespace BizHawk.Client.Common.cheats
 		private static IDecodeResult GameBoy(string code)
 		{
 			// Game Genie
-			if (code.LastIndexOf("-") == 7 && code.IndexOf("-") == 3)
+			if (code.LastIndexOf("-", StringComparison.Ordinal) == 7 && code.IndexOf("-", StringComparison.Ordinal) == 3)
 			{
 				return GbGgGameGenieDecoder.Decode(code);
 			}
@@ -87,7 +89,7 @@ namespace BizHawk.Client.Common.cheats
 			{
 				// Problem: I don't know what the Non-FF Style codes are.
 				// TODO: Fix that.
-				if (code.StartsWith("FF") == false)
+				if (code.StartsWithOrdinal("FF") == false)
 				{
 					return new InvalidCheatCode("This Action Replay Code, is not yet supported.");
 				}
@@ -109,13 +111,13 @@ namespace BizHawk.Client.Common.cheats
 		private static IDecodeResult Sms(string code)
 		{
 			// Game Genie
-			if (code.LastIndexOf("-") == 7 && code.IndexOf("-") == 3)
+			if (code.LastIndexOf("-", StringComparison.Ordinal) == 7 && code.IndexOf("-", StringComparison.Ordinal) == 3)
 			{
 				return GbGgGameGenieDecoder.Decode(code);
 			}
 
 			// Action Replay
-			if (code.IndexOf("-") == 3 && code.Length == 9)
+			if (code.IndexOf("-", StringComparison.Ordinal) == 3 && code.Length == 9)
 			{
 				return SmsActionReplayDecoder.Decode(code);
 			}

src/BizHawk.Client.Common/cheats/GbGgGameGenieDecoder.cs

@@ -35,7 +35,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(_code));
 			}
 
-			if (_code.LastIndexOf("-") != 7 || _code.IndexOf("-") != 3)
+			if (_code.LastIndexOf("-", StringComparison.Ordinal) != 7 || _code.IndexOf("-", StringComparison.Ordinal) != 3)
 			{
 				return new InvalidCheatCode("All Master System Game Genie Codes need to have a dash after the third character and seventh character.");
 			}

src/BizHawk.Client.Common/cheats/GbaGameSharkDecoder.cs

@@ -57,7 +57,7 @@ namespace BizHawk.Client.Common.cheats
 				code = Decrypt(code);
 			}
 
-			if (code.IndexOf(" ") != 8 || code.Length != 17) // not a redundant length check, `code` was overwritten
+			if (code.IndexOf(" ", StringComparison.Ordinal) != 8 || code.Length != 17) // not a redundant length check, `code` was overwritten
 			{
 				return new InvalidCheatCode("All GBA GameShark Codes need to be 17 characters in length with a space after the first eight.");
 			}

src/BizHawk.Client.Common/cheats/GenesisActionReplayDecoder.cs

@@ -13,7 +13,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 
-			if (code.IndexOf(":") != 6)
+			if (code.IndexOf(":", StringComparison.Ordinal) != 6)
 			{
 				return new InvalidCheatCode("Action Replay/Pro Action Replay Codes need to contain a colon after the sixth character.");
 			}

src/BizHawk.Client.Common/cheats/GenesisGameGenieDecoder.cs

@@ -48,7 +48,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 
-			if (code.IndexOf("-") != 4)
+			if (code.IndexOf("-", StringComparison.Ordinal) != 4)
 			{
 				return new InvalidCheatCode("Game Genie Codes need to contain a dash after the fourth character");
 			}

src/BizHawk.Client.Common/cheats/N64GameSharkDecoder.cs

@@ -13,7 +13,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 			
-			if (code.IndexOf(" ") != 8)
+			if (code.IndexOf(" ", StringComparison.Ordinal) != 8)
 			{
 				return new InvalidCheatCode("GameShark Codes need to contain a space after the eighth character.");
 			}

src/BizHawk.Client.Common/cheats/PsxGameSharkDecoder.cs

@@ -14,7 +14,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 
-			if (code.IndexOf(" ") != 8)
+			if (code.IndexOf(" ", StringComparison.Ordinal) != 8)
 			{
 				return new InvalidCheatCode("All PSX GameShark Codes need to contain a space after the eighth character.");
 			}

src/BizHawk.Client.Common/cheats/SaturnGameSharkDecoder.cs

@@ -18,7 +18,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 
-			if (code.IndexOf(" ") != 8)
+			if (code.IndexOf(" ", StringComparison.Ordinal) != 8)
 			{
 				return new InvalidCheatCode("All Saturn GameShark Codes need to contain a space after the eighth character.");
 			}

src/BizHawk.Client.Common/cheats/SmsActionReplayDecoder.cs

@@ -12,7 +12,7 @@ namespace BizHawk.Client.Common.cheats
 				throw new ArgumentNullException(nameof(code));
 			}
 
-			if (code.IndexOf("-") != 3 && code.Length != 9)
+			if (code.IndexOf("-", StringComparison.Ordinal) != 3 && code.Length != 9)
 			{
 				return new InvalidCheatCode("Action Replay Codes must be 9 characters with a dash after the third character");
 			}

src/BizHawk.Client.Common/config/PathEntryCollectionExtensions.cs

@@ -90,12 +90,12 @@ namespace BizHawk.Client.Common
 
 			if (path == "%recent%") return PathUtils.SpecialRecentsDir;
 
-			if (path.StartsWith("%exe%"))
+			if (path.StartsWithOrdinal("%exe%"))
 			{
 				return PathUtils.ExeDirectoryPath + path.Substring(5);
 			}
 
-			if (path.StartsWith("%rom%"))
+			if (path.StartsWithOrdinal("%rom%"))
 			{
 				return collection.LastRomPath + path.Substring(5);
 			}

src/BizHawk.Client.Common/input/InputCoalescerControllers.cs

@@ -1,6 +1,7 @@
 #nullable enable
 
 using System.Linq;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.Common
@@ -21,7 +22,7 @@ namespace BizHawk.Client.Common
 			if (state) return;
 			// when a button or modifier key is released, all modified key variants with it are released as well
 			foreach (var k in Buttons.Keys.Where(k =>
-						k.EndsWith($"+{ie.LogicalButton.Button}") || k.StartsWith($"{ie.LogicalButton.Button}+") || k.Contains($"+{ie.LogicalButton.Button}+"))
+						k.EndsWithOrdinal($"+{ie.LogicalButton.Button}") || k.StartsWithOrdinal($"{ie.LogicalButton.Button}+") || k.Contains($"+{ie.LogicalButton.Button}+"))
 						.ToArray())
 				Buttons[k] = false;
 		}

src/BizHawk.Client.Common/lua/CommonLibs/ClientLuaLibrary.cs

@@ -330,7 +330,7 @@ namespace BizHawk.Client.Common
 		[LuaMethodExample("local nlcliget = client.getavailabletools( );")]
 		[LuaMethod("getavailabletools", "Returns a list of the tools currently open")]
 		public LuaTable GetAvailableTools()
-			=> _th.EnumerateToLuaTable(APIs.Tool.AvailableTools.Select(tool => tool.Name.ToLower()), indexFrom: 0);
+			=> _th.EnumerateToLuaTable(APIs.Tool.AvailableTools.Select(tool => tool.Name.ToLowerInvariant()), indexFrom: 0);
 
 		[LuaMethodExample("local nlcliget = client.gettool( \"Tool name\" );")]
 		[LuaMethod("gettool", "Returns an object that represents a tool of the given name (not case sensitive). If the tool is not open, it will be loaded if available. Use getavailabletools to get a list of names")]

src/BizHawk.Client.Common/lua/LuaDocumentation.cs

@@ -290,7 +290,7 @@ namespace BizHawk.Client.Common
 				.Replace("Uint", "uint ")
 				.Replace("Nullable`1[DrawingColor]", "Color? ")
 				.Replace("DrawingColor", "Color ")
-				.ToLower();
+				.ToLowerInvariant();
 		}
 
 		public string ReturnType

src/BizHawk.Client.Common/lua/LuaFileList.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.IO;
 using System.Text;
 using BizHawk.Common.PathExtensions;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Client.Common
 {
@@ -78,7 +79,7 @@ namespace BizHawk.Client.Common
 			string line;
 			while ((line = sr.ReadLine()) != null)
 			{
-				if (line.StartsWith("---"))
+				if (line.StartsWithOrdinal("---"))
 				{
 					Add(LuaFile.SeparatorInstance);
 				}

src/BizHawk.Client.Common/lua/LuaHelperLibs/StringLuaLibrary.cs

@@ -1,7 +1,7 @@
 using System;
 using System.ComponentModel;
 using System.Linq;
-
+using BizHawk.Common.StringExtensions;
 using NLua;
 
 // ReSharper disable UnusedMember.Global
@@ -127,12 +127,12 @@ namespace BizHawk.Client.Common
 		[LuaMethodExample("if ( bizstring.startswith( \"Some string\", \"Some\") ) then\r\n\tconsole.log( \"Returns whether str starts with str2\" );\r\nend;")]
 		[LuaMethod("startswith", "Returns whether str starts with str2")]
 		public static bool StartsWith(string str, string str2)
-			=> !string.IsNullOrEmpty(str) && str.StartsWith(str2); // don't bother fixing encoding, will match (or not match) regardless
+			=> !string.IsNullOrEmpty(str) && str.StartsWithOrdinal(str2); // don't bother fixing encoding, will match (or not match) regardless
 
 		[LuaMethodExample("if ( bizstring.endswith( \"Some string\", \"string\") ) then\r\n\tconsole.log( \"Returns whether str ends wth str2\" );\r\nend;")]
 		[LuaMethod("endswith", "Returns whether str ends wth str2")]
 		public static bool EndsWith(string str, string str2)
-			=> !string.IsNullOrEmpty(str) && str.EndsWith(str2); // don't bother fixing encoding, will match (or not match) regardless
+			=> !string.IsNullOrEmpty(str) && str.EndsWithOrdinal(str2); // don't bother fixing encoding, will match (or not match) regardless
 
 		[LuaMethodExample("local nlbizspl = bizstring.split( \"Some, string\", \", \" );")]
 		[LuaMethod("split", "Splits str into a Lua-style array using the given separator (consecutive separators in str will NOT create empty entries in the array). If the separator is not a string exactly one char long, ',' will be used.")]

src/BizHawk.Client.Common/movie/MovieService.cs

@@ -18,7 +18,7 @@ namespace BizHawk.Client.Common
 
 		public static bool IsValidMovieExtension(string ext)
 		{
-			return MovieExtensions.Contains(ext.ToLower().Replace(".", ""));
+			return MovieExtensions.Contains(ext.Replace(".", ""), StringComparer.OrdinalIgnoreCase);
 		}
 
 		public static bool IsCurrentTasVersion(string movieVersion)
@@ -35,7 +35,7 @@ namespace BizHawk.Client.Common
 			}
 
 			var split = movieVersion
-				.ToLower()
+				.ToLowerInvariant()
 				.Split(new[] {"tasproj"}, StringSplitOptions.RemoveEmptyEntries);
 
 			if (split.Length == 1)

src/BizHawk.Client.Common/movie/MovieSession.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.Common
@@ -307,7 +308,7 @@ namespace BizHawk.Client.Common
 		public IMovie Get(string path)
 		{
 			// TODO: change IMovies to take HawkFiles only and not path
-			if (Path.GetExtension(path)?.EndsWith("tasproj") ?? false)
+			if (Path.GetExtension(path)?.EndsWithOrdinal("tasproj") ?? false)
 			{
 				return new TasMovie(this, path);
 			}

src/BizHawk.Client.Common/movie/bk2/Bk2Movie.IO.cs

@@ -23,7 +23,7 @@ namespace BizHawk.Client.Common
 			}
 
 			var backupName = Filename;
-			backupName = backupName.Insert(Filename.LastIndexOf("."), $".{DateTime.Now:yyyy-MM-dd HH.mm.ss}");
+			backupName = backupName.Insert(Filename.LastIndexOf(".", StringComparison.Ordinal), $".{DateTime.Now:yyyy-MM-dd HH.mm.ss}");
 			backupName = Path.Combine(Session.BackupDirectory, Path.GetFileName(backupName));
 
 			Write(backupName, isBackup: true);

src/BizHawk.Client.Common/movie/bk2/Bk2Movie.InputLog.cs

@@ -58,7 +58,7 @@ namespace BizHawk.Client.Common
 				{
 					Log.Add(line);
 				}
-				else if (line.StartsWith("Frame "))
+				else if (line.StartsWithOrdinal("Frame "))
 				{
 					var strs = line.Split(' ');
 					try
@@ -71,7 +71,7 @@ namespace BizHawk.Client.Common
 						return false;
 					}
 				}
-				else if (line.StartsWith("LogKey:"))
+				else if (line.StartsWithOrdinal("LogKey:"))
 				{
 					LogKey = line.Replace("LogKey:", "");
 				}
@@ -122,7 +122,7 @@ namespace BizHawk.Client.Common
 				{
 					newLog.Add(line);
 				}
-				else if (line.StartsWith("Frame "))
+				else if (line.StartsWithOrdinal("Frame "))
 				{
 					var strs = line.Split(' ');
 					try

src/BizHawk.Client.Common/movie/import/DsmImport.cs

@@ -2,6 +2,7 @@
 using System.Globalization;
 using System.Linq;
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores;
 using BizHawk.Emulation.Cores.Consoles.Nintendo.NDS;
@@ -41,40 +42,40 @@ namespace BizHawk.Client.Common
 				{
 					ImportInputFrame(line);
 				}
-				else if (line.StartsWith("rerecordCount"))
+				else if (line.StartsWithOrdinal("rerecordCount"))
 				{
 					Result.Movie.Rerecords = (ulong) (int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount) ? rerecordCount : default);
 				}
-				else if (line.StartsWith("firmNickname"))
+				else if (line.StartsWithOrdinal("firmNickname"))
 				{
 					syncSettings.FirmwareUsername = ParseHeader(line, "firmNickname");
 				}
-				else if (line.StartsWith("firmFavColour"))
+				else if (line.StartsWithOrdinal("firmFavColour"))
 				{
 					syncSettings.FirmwareFavouriteColour = (NDS.NDSSyncSettings.Color)byte.Parse(ParseHeader(line, "firmFavColour"));
 				}
-				else if (line.StartsWith("firmBirthDay"))
+				else if (line.StartsWithOrdinal("firmBirthDay"))
 				{
 					syncSettings.FirmwareBirthdayDay = byte.Parse(ParseHeader(line, "firmBirthDay"));
 				}
-				else if (line.StartsWith("firmBirthMonth"))
+				else if (line.StartsWithOrdinal("firmBirthMonth"))
 				{
 					syncSettings.FirmwareBirthdayMonth = (NDS.NDSSyncSettings.Month)byte.Parse(ParseHeader(line, "firmBirthMonth"));
 				}
-				else if (line.StartsWith("rtcStartNew"))
+				else if (line.StartsWithOrdinal("rtcStartNew"))
 				{
 					string rtcTime = ParseHeader(line, "rtcStartNew");
 					syncSettings.InitialTime = DateTime.ParseExact(rtcTime, "yyyy'-'MMM'-'dd' 'HH':'mm':'ss':'fff", DateTimeFormatInfo.InvariantInfo);
 				}
-				else if (line.StartsWith("comment author"))
+				else if (line.StartsWithOrdinal("comment author"))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.Author] = ParseHeader(line, "comment author");
 				}
-				else if (line.StartsWith("comment"))
+				else if (line.StartsWithOrdinal("comment"))
 				{
 					Result.Movie.Comments.Add(ParseHeader(line, "comment"));
 				}
-				else if (line.ToLower().StartsWith("guid"))
+				else if (line.StartsWith("guid", StringComparison.OrdinalIgnoreCase))
 				{
 					// We no longer care to keep this info
 				}

src/BizHawk.Client.Common/movie/import/FcmImport.cs

@@ -107,7 +107,7 @@ namespace BizHawk.Client.Common.movie.import
 
 			// 020 16-byte md5sum of the ROM used
 			byte[] md5 = r.ReadBytes(16);
-			Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLower();
+			Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLowerInvariant();
 
 			// 030 4-byte little-endian unsigned int: version of the emulator used
 			uint emuVersion = r.ReadUInt32();

src/BizHawk.Client.Common/movie/import/Fm2Import.cs

@@ -44,7 +44,7 @@ namespace BizHawk.Client.Common
 				{
 					ImportInputFrame(line);
 				}
-				else if (line.ToLower().StartsWith("sub"))
+				else if (line.StartsWith("sub", StringComparison.OrdinalIgnoreCase))
 				{
 					var subtitle = ImportTextSubtitle(line);
 
@@ -53,11 +53,11 @@ namespace BizHawk.Client.Common
 						Result.Movie.Subtitles.AddFromString(subtitle);
 					}
 				}
-				else if (line.ToLower().StartsWith("emuversion"))
+				else if (line.StartsWith("emuversion", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.Comments.Add($"{EmulationOrigin} {emulator} version {ParseHeader(line, "emuVersion")}");
 				}
-				else if (line.ToLower().StartsWith("version"))
+				else if (line.StartsWith("version", StringComparison.OrdinalIgnoreCase))
 				{
 					string version = ParseHeader(line, "version");
 
@@ -70,40 +70,40 @@ namespace BizHawk.Client.Common
 						Result.Movie.Comments.Add($"{MovieOrigin} .fm2 version 3");
 					}
 				}
-				else if (line.ToLower().StartsWith("romfilename"))
+				else if (line.StartsWith("romfilename", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.GameName] = ParseHeader(line, "romFilename");
 				}
-				else if (line.ToLower().StartsWith("cdgamename"))
+				else if (line.StartsWith("cdgamename", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.GameName] = ParseHeader(line, "cdGameName");
 				}
-				else if (line.ToLower().StartsWith("romchecksum"))
+				else if (line.StartsWith("romchecksum", StringComparison.OrdinalIgnoreCase))
 				{
 					string blob = ParseHeader(line, "romChecksum");
 					byte[] md5 = DecodeBlob(blob);
 					if (md5 != null && md5.Length == 16)
 					{
-						Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLower();
+						Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLowerInvariant();
 					}
 					else
 					{
 						Result.Warnings.Add("Bad ROM checksum.");
 					}
 				}
-				else if (line.ToLower().StartsWith("comment author"))
+				else if (line.StartsWith("comment author", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.Author] = ParseHeader(line, "comment author");
 				}
-				else if (line.ToLower().StartsWith("rerecordcount"))
+				else if (line.StartsWith("rerecordcount", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.Rerecords = (ulong) (int.TryParse(ParseHeader(line, "rerecordCount"), out var rerecordCount) ? rerecordCount : default);
 				}
-				else if (line.ToLower().StartsWith("guid"))
+				else if (line.StartsWith("guid", StringComparison.OrdinalIgnoreCase))
 				{
 					// We no longer care to keep this info
 				}
-				else if (line.ToLower().StartsWith("startsfromsavestate"))
+				else if (line.StartsWith("startsfromsavestate", StringComparison.OrdinalIgnoreCase))
 				{
 					// If this movie starts from a savestate, we can't support it.
 					if (ParseHeader(line, "StartsFromSavestate") == "1")
@@ -112,11 +112,11 @@ namespace BizHawk.Client.Common
 						break;
 					}
 				}
-				else if (line.ToLower().StartsWith("palflag"))
+				else if (line.StartsWith("palflag", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.Pal] = ParseHeader(line, "palFlag");
 				}
-				else if (line.ToLower().StartsWith("port0"))
+				else if (line.StartsWith("port0", StringComparison.OrdinalIgnoreCase))
 				{
 					if (ParseHeader(line, "port0") == "1")
 					{
@@ -124,7 +124,7 @@ namespace BizHawk.Client.Common
 						_deck = controllerSettings.Instantiate((x, y) => false).AddSystemToControllerDef();
 					}
 				}
-				else if (line.ToLower().StartsWith("port1"))
+				else if (line.StartsWith("port1", StringComparison.OrdinalIgnoreCase))
 				{
 					if (ParseHeader(line, "port1") == "1")
 					{
@@ -132,14 +132,14 @@ namespace BizHawk.Client.Common
 						_deck = controllerSettings.Instantiate((x, y) => false).AddSystemToControllerDef();
 					}
 				}
-				else if (line.ToLower().StartsWith("port2"))
+				else if (line.StartsWith("port2", StringComparison.OrdinalIgnoreCase))
 				{
 					if (ParseHeader(line, "port2") == "1")
 					{
 						Result.Warnings.Add("Famicom port detected but not yet supported, ignoring");
 					}
 				}
-				else if (line.ToLower().StartsWith("fourscore"))
+				else if (line.StartsWith("fourscore", StringComparison.OrdinalIgnoreCase))
 				{
 					bool fourscore = ParseHeader(line, "fourscore") == "1";
 					if (fourscore)
@@ -162,7 +162,7 @@ namespace BizHawk.Client.Common
 		}
 
 		private IControllerDeck _deck;
-		
+
 		private readonly string[] _buttons = { "Right", "Left", "Down", "Up", "Start", "Select", "B", "A" };
 		private void ImportInputFrame(string line)
 		{
@@ -244,7 +244,7 @@ namespace BizHawk.Client.Common
 			}
 
 			// base64
-			if (!blob.ToLower().StartsWith("base64:"))
+			if (!blob.StartsWith("base64:", StringComparison.OrdinalIgnoreCase))
 			{
 				return null;
 			}

src/BizHawk.Client.Common/movie/import/IMovieImport.cs

@@ -117,8 +117,7 @@ namespace BizHawk.Client.Common
 		protected static string ParseHeader(string line, string headerName)
 		{
 			// Case-insensitive search.
-			int x = line.ToLower().LastIndexOf(
-				headerName.ToLower()) + headerName.Length;
+			int x = line.LastIndexOf(headerName, StringComparison.OrdinalIgnoreCase) + headerName.Length;
 			string str = line.Substring(x + 1, line.Length - x - 1);
 			return str.Trim();
 		}

src/BizHawk.Client.Common/movie/import/LsmvImport.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.IO;
 using System.IO.Compression;
 using System.Linq;
@@ -177,7 +178,7 @@ namespace BizHawk.Client.Common.movie.import
 					}
 					Result.Movie.AppendFrame(_previousControllers);
 				}
-				else if (item.FullName.StartsWith("moviesram."))
+				else if (item.FullName.StartsWithOrdinal("moviesram."))
 				{
 					using var stream = item.Open();
 					byte[] movieSram = stream.ReadAllBytes();
@@ -212,7 +213,7 @@ namespace BizHawk.Client.Common.movie.import
 
 					Result.Movie.Rerecords = rerecordCount;
 				}
-				else if (item.FullName.EndsWith(".sha256"))
+				else if (item.FullName.EndsWithOrdinal(".sha256"))
 				{
 					using var stream = item.Open();
 					string sha256Hash = Encoding.UTF8.GetString(stream.ReadAllBytes()).Trim();
@@ -318,7 +319,7 @@ namespace BizHawk.Client.Common.movie.import
 				if (player > _playerCount) break;
 
 				IReadOnlyList<string> buttons = controllers.Definition.ControlsOrdered[player];
-				if (buttons[0].EndsWith("Up")) // hack to identify gamepad / multitap which have a different button order in bizhawk compared to lsnes
+				if (buttons[0].EndsWithOrdinal("Up")) // hack to identify gamepad / multitap which have a different button order in bizhawk compared to lsnes
 				{
 					buttons = new[] { "B", "Y", "Select", "Start", "Up", "Down", "Left", "Right", "A", "X", "L", "R" }
 						.Select(button => $"P{player} {button}")

src/BizHawk.Client.Common/movie/import/Mc2Import.cs

@@ -1,4 +1,5 @@
-using BizHawk.Emulation.Common;
+using System;
+using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores.PCEngine;
 
 namespace BizHawk.Client.Common.movie.import
@@ -43,8 +44,7 @@ namespace BizHawk.Client.Common.movie.import
 				{
 					ImportTextFrame(line);
 				}
-				else if (line.ToLower()
-					.StartsWith("ports"))
+				else if (line.StartsWith("ports", StringComparison.OrdinalIgnoreCase))
 				{
 					var portNumStr = ParseHeader(line, "ports");
 					if (int.TryParse(portNumStr, out int ports))
@@ -83,32 +83,32 @@ namespace BizHawk.Client.Common.movie.import
 							ss.Port5);
 					}
 				}
-				else if (line.ToLower().StartsWith("pcecd"))
+				else if (line.StartsWith("pcecd", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.Platform] = VSystemID.Raw.PCECD;
 				}
-				else if (line.ToLower().StartsWith("emuversion"))
+				else if (line.StartsWith("emuversion", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.Comments.Add($"{EmulationOrigin} Mednafen/PCEjin version {ParseHeader(line, "emuVersion")}");
 				}
-				else if (line.ToLower().StartsWith("version"))
+				else if (line.StartsWith("version", StringComparison.OrdinalIgnoreCase))
 				{
 					string version = ParseHeader(line, "version");
 					Result.Movie.Comments.Add($"{MovieOrigin} .mc2 version {version}");
 				}
-				else if (line.ToLower().StartsWith("romfilename"))
+				else if (line.StartsWith("romfilename", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.GameName] = ParseHeader(line, "romFilename");
 				}
-				else if (line.ToLower().StartsWith("cdgamename"))
+				else if (line.StartsWith("cdgamename", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.GameName] = ParseHeader(line, "cdGameName");
 				}
-				else if (line.ToLower().StartsWith("comment author"))
+				else if (line.StartsWith("comment author", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.Author] = ParseHeader(line, "comment author");
 				}
-				else if (line.ToLower().StartsWith("rerecordcount"))
+				else if (line.StartsWith("rerecordcount", StringComparison.OrdinalIgnoreCase))
 				{
 					int rerecordCount;
 
@@ -124,7 +124,7 @@ namespace BizHawk.Client.Common.movie.import
 
 					Result.Movie.Rerecords = (ulong)rerecordCount;
 				}
-				else if (line.ToLower().StartsWith("startsfromsavestate"))
+				else if (line.StartsWith("startsfromsavestate", StringComparison.OrdinalIgnoreCase))
 				{
 					// If this movie starts from a savestate, we can't support it.
 					if (ParseHeader(line, "StartsFromSavestate") == "1")

src/BizHawk.Client.Common/movie/import/MmvImport.cs

@@ -35,7 +35,7 @@ namespace BizHawk.Client.Common.movie.import
 			uint rerecordCount = r.ReadUInt32();
 			Result.Movie.Rerecords = rerecordCount;
 
-			
+
 			// 0010: 4-byte little endian flag: begin from reset?
 			uint reset = r.ReadUInt32();
 			if (reset == 0)
@@ -92,7 +92,7 @@ namespace BizHawk.Client.Common.movie.import
 
 			// 00e4-00f3: binary: rom MD5 digest
 			byte[] md5 = r.ReadBytes(16);
-			Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLower();
+			Result.Movie.HeaderEntries[HeaderKeys.Md5] = md5.BytesToHexString().ToLowerInvariant();
 
 			var ss = new SMS.SmsSyncSettings();
 			var cd = new SMSControllerDeck(ss.Port1, ss.Port2, isGameGear, ss.UseKeyboard);

src/BizHawk.Client.Common/movie/import/PjmImport.cs

@@ -1,5 +1,5 @@
 using System.IO;
-
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores.Sony.PSX;
 
@@ -315,7 +315,7 @@ namespace BizHawk.Client.Common
 				}
 
 				// Gross, if not CR LF, this will fail, but will the PSXjin?
-				if (!mnemonicStr.EndsWith("|\r\n"))
+				if (!mnemonicStr.EndsWithOrdinal("|\r\n"))
 				{
 					Result.Errors.Add("Unable to parse text input, unknown configuration");
 				}

src/BizHawk.Client.Common/movie/import/YmvImport.cs

@@ -45,20 +45,20 @@ namespace BizHawk.Client.Common.movie.import
 				{
 					ImportTextFrame(line);
 				}
-				else if (line.ToLower().StartsWith("emuversion"))
+				else if (line.StartsWith("emuversion", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.Comments.Add($"{EmulationOrigin} Yabause version {ParseHeader(line, "emuVersion")}");
 				}
-				else if (line.ToLower().StartsWith("version"))
+				else if (line.StartsWith("version", StringComparison.OrdinalIgnoreCase))
 				{
 					string version = ParseHeader(line, "version");
 					Result.Movie.Comments.Add($"{MovieOrigin} .ymv version {version}");
 				}
-				else if (line.ToLower().StartsWith("cdGameName"))
+				else if (line.StartsWith("cdGameName", StringComparison.OrdinalIgnoreCase))
 				{
 					Result.Movie.HeaderEntries[HeaderKeys.GameName] = ParseHeader(line, "romFilename");
 				}
-				else if (line.ToLower().StartsWith("rerecordcount"))
+				else if (line.StartsWith("rerecordcount", StringComparison.OrdinalIgnoreCase))
 				{
 					int rerecordCount;
 
@@ -74,7 +74,7 @@ namespace BizHawk.Client.Common.movie.import
 
 					Result.Movie.Rerecords = (ulong)rerecordCount;
 				}
-				else if (line.ToLower().StartsWith("startsfromsavestate"))
+				else if (line.StartsWith("startsfromsavestate", StringComparison.OrdinalIgnoreCase))
 				{
 					// If this movie starts from a savestate, we can't support it.
 					if (ParseHeader(line, "StartsFromSavestate") == "1")
@@ -82,7 +82,7 @@ namespace BizHawk.Client.Common.movie.import
 						Result.Errors.Add("Movies that begin with a savestate are not supported.");
 					}
 				}
-				else if (line.ToLower().StartsWith("ispal"))
+				else if (line.StartsWith("ispal", StringComparison.OrdinalIgnoreCase))
 				{
 					bool pal = ParseHeader(line, "isPal") == "1";
 					Result.Movie.HeaderEntries[HeaderKeys.Pal] = pal.ToString();

src/BizHawk.Client.Common/movie/import/bkm/BkmHeader.cs

@@ -56,11 +56,11 @@ namespace BizHawk.Client.Common
 				{
 					Add(splitLine[0], splitLine[1]);
 				}
-				else if (line.StartsWith("subtitle") || line.StartsWith("sub"))
+				else if (line.StartsWithOrdinal("subtitle") || line.StartsWithOrdinal("sub"))
 				{
 					Subtitles.AddFromString(line);
 				}
-				else if (line.StartsWith("comment"))
+				else if (line.StartsWithOrdinal("comment"))
 				{
 					Comments.Add(line.Substring(8, line.Length - 8));
 				}

src/BizHawk.Client.Common/movie/tasproj/TasMovie.cs

@@ -238,7 +238,7 @@ namespace BizHawk.Client.Common
 
 					counter++;
 				}
-				else if (line.StartsWith("Frame "))
+				else if (line.StartsWithOrdinal("Frame "))
 				{
 					var split = line.Split(' ');
 					try
@@ -251,7 +251,7 @@ namespace BizHawk.Client.Common
 						return false;
 					}
 				}
-				else if (line.StartsWith("LogKey:"))
+				else if (line.StartsWithOrdinal("LogKey:"))
 				{
 					LogKey = line.Replace("LogKey:", "");
 				}
@@ -327,7 +327,7 @@ namespace BizHawk.Client.Common
 				if (_changes != value)
 				{
 					_changes = value;
-					OnPropertyChanged("Changes");
+					OnPropertyChanged(nameof(Changes));
 				}
 			}
 		}

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchAddressComparer.cs

@@ -32,12 +32,12 @@ namespace BizHawk.Client.Common
 
 				if (x.Address.Equals(y.Address))
 				{
-					if (x.Domain.Name.Equals(y.Domain.Name))
+					if (x.Domain.Name.Equals(y.Domain.Name, System.StringComparison.Ordinal))
 					{
 						return x.Size.CompareTo(y.Size);
 					}
 
-					return x.Domain.Name.CompareTo(y.Domain.Name);
+					return string.CompareOrdinal(x.Domain.Name, y.Domain.Name);
 				}
 
 				return x.Address.CompareTo(y.Address);

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchDomainComparer.cs

@@ -30,7 +30,7 @@ namespace BizHawk.Client.Common
 					return 0;
 				}
 
-				if (x.Domain.Name.Equals(y.Domain.Name))
+				if (x.Domain.Name.Equals(y.Domain.Name, System.StringComparison.Ordinal))
 				{
 					if (x.Address.Equals(y.Address))
 					{
@@ -40,7 +40,7 @@ namespace BizHawk.Client.Common
 					return x.Address.CompareTo(y.Address);
 				}
 
-				return x.Domain.Name.CompareTo(y.Domain.Name);
+				return string.CompareOrdinal(x.Domain.Name, y.Domain.Name);
 			}
 		}
 	}

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchNoteComparer.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 
 namespace BizHawk.Client.Common
 {
@@ -31,7 +32,7 @@ namespace BizHawk.Client.Common
 					return 0;
 				}
 
-				if (string.Compare(x.Notes, y.Notes, true) == 0)
+				if (string.Compare(x.Notes, y.Notes, StringComparison.OrdinalIgnoreCase) == 0)
 				{
 					if (x.Address.Equals(y.Address))
 					{
@@ -41,7 +42,7 @@ namespace BizHawk.Client.Common
 					return x.Address.CompareTo(y.Address);
 				}
 
-				return string.Compare(x.Notes, y.Notes, true);
+				return string.Compare(x.Notes, y.Notes, StringComparison.OrdinalIgnoreCase);
 			}
 		}
 	}

src/BizHawk.Client.Common/tools/Watch/WatchList/WatchValueDifferenceComparer.cs

@@ -30,7 +30,7 @@ namespace BizHawk.Client.Common
 					return 0;
 				}
 
-				if (x.Diff.Equals(y.Diff))
+				if (x.Diff.Equals(y.Diff, System.StringComparison.Ordinal))
 				{
 					if (x.Address.Equals(y.Address))
 					{
@@ -40,7 +40,7 @@ namespace BizHawk.Client.Common
 					return x.Address.CompareTo(y.Address);
 				}
 
-				return x.Diff.CompareTo(y.Diff);
+				return string.CompareOrdinal(x.Diff, y.Diff);
 			}
 		}
 	}

src/BizHawk.Client.EmuHawk/AVOut/ImageSequenceWriter.cs

@@ -50,11 +50,11 @@ namespace BizHawk.Client.EmuHawk
 			var name = Path.Combine(dir!, $"{fileNoExt}_{_frame}{ext}");
 			BitmapBuffer bb = new BitmapBuffer(source.BufferWidth, source.BufferHeight, source.GetVideoBuffer());
 			using var bmp = bb.ToSysdrawingBitmap();
-			if (ext.ToUpper() == ".PNG")
+			if (ext.ToUpperInvariant() == ".PNG")
 			{
 				bmp.Save(name, ImageFormat.Png);
 			}
-			else if (ext.ToUpper() == ".JPG")
+			else if (ext.ToUpperInvariant() == ".JPG")
 			{
 				bmp.Save(name, ImageFormat.Jpeg);
 			}

src/BizHawk.Client.EmuHawk/AVOut/JMDWriter.cs

@@ -602,7 +602,7 @@ namespace BizHawk.Client.EmuHawk
 		public void OpenFile(string baseName)
 		{
 			string ext = Path.GetExtension(baseName);
-			if (ext == null || ext.ToLower() != ".jmd")
+			if (ext == null || ext.ToLowerInvariant() != ".jmd")
 			{
 				baseName += ".jmd";
 			}

src/BizHawk.Client.EmuHawk/AVOut/NumericTextBox.cs

@@ -23,15 +23,15 @@ namespace BizHawk.Client.EmuHawk
 			{
 				// Digits are OK
 			}
-			else if (keyInput.Equals(decimalSeparator) && AllowDecimal)
+			else if (keyInput.Equals(decimalSeparator, System.StringComparison.Ordinal) && AllowDecimal)
 			{
 				// Decimal separator is OK
 			}
-			else if (keyInput.Equals(negativeSign) && AllowNegative)
+			else if (keyInput.Equals(negativeSign, System.StringComparison.Ordinal) && AllowNegative)
 			{
 				// Negative is OK
 			}
-			else if (keyInput.Equals(groupSeparator))
+			else if (keyInput.Equals(groupSeparator, System.StringComparison.Ordinal))
 			{
 				// group separator is ok
 			}

src/BizHawk.Client.EmuHawk/ArchiveChooser.cs

@@ -35,7 +35,7 @@ namespace BizHawk.Client.EmuHawk
 				lvi.Text = item.Name;
 				long size = item.Size;
 				var extension = Path.GetExtension(item.Name);
-				if (extension != null && size % 1024 == 16 && extension.ToUpper() == ".NES")
+				if (extension != null && size % 1024 == 16 && extension.ToUpperInvariant() == ".NES")
 					size -= 16;
 				lvi.SubItems[1].Text = Util.FormatFileSize(size);
 				_archiveItems.Add(lvi);
@@ -206,7 +206,7 @@ namespace BizHawk.Client.EmuHawk
 			public string[] Keys { get; set; }
 			public bool Matches(ListViewItem value)
 			{
-				string searchedStr = value.Text.ToLower();
+				string searchedStr = value.Text.ToLowerInvariant();
 				foreach (string key in Keys)
 				{
 					if (!searchedStr.Contains(key))
@@ -234,7 +234,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				return new SimpleMatcher
 				{
-					Keys = searchKey.ToLower().Split(Array.Empty<char>(), StringSplitOptions.RemoveEmptyEntries) // splits on all whitespace chars
+					Keys = searchKey.ToLowerInvariant().Split(Array.Empty<char>(), StringSplitOptions.RemoveEmptyEntries) // splits on all whitespace chars
 				};
 			}
 			else

src/BizHawk.Client.EmuHawk/CustomControls/InputRoll/Cell.cs

@@ -71,7 +71,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					int row = c1.RowIndex.Value.CompareTo(c2.RowIndex.Value);
 					return row == 0
-						? string.Compare(c1.Column?.Name, c2.Column?.Name)
+						? string.CompareOrdinal(c1.Column?.Name, c2.Column?.Name)
 						: row;
 				}
 					
@@ -83,7 +83,7 @@ namespace BizHawk.Client.EmuHawk
 				return -1;
 			}
 
-			return c1.Column.Name.CompareTo(c2.Column.Name);
+			return string.CompareOrdinal(c1.Column.Name, c2.Column.Name);
 		}
 	}
 

src/BizHawk.Client.EmuHawk/EmuHawkUtil.cs

@@ -15,7 +15,7 @@ namespace BizHawk.Client.EmuHawk
 		/// <remarks>http://stackoverflow.com/questions/139010/how-to-resolve-a-lnk-in-c-sharp</remarks>
 		public static string ResolveShortcut(string filename)
 		{
-			if (filename.Contains("|") || OSTailoredCode.IsUnixHost || !".lnk".Equals(Path.GetExtension(filename), StringComparison.InvariantCultureIgnoreCase)) return filename; // archive internal files are never shortcuts (and choke when analyzing any further)
+			if (filename.Contains("|") || OSTailoredCode.IsUnixHost || !".lnk".Equals(Path.GetExtension(filename), StringComparison.OrdinalIgnoreCase)) return filename; // archive internal files are never shortcuts (and choke when analyzing any further)
 			var link = new ShellLinkImports.ShellLink();
 			const uint STGM_READ = 0;
 			((ShellLinkImports.IPersistFile) link).Load(filename, STGM_READ);

src/BizHawk.Client.EmuHawk/Extensions/ControlExtensions.cs

@@ -250,7 +250,7 @@ namespace BizHawk.Client.EmuHawk
 				initFileName: $"{game.FilesystemSafeName()}-{suffix}");
 			if (result is null) return;
 			FileInfo file = new(result);
-			string extension = file.Extension.ToUpper();
+			string extension = file.Extension.ToUpperInvariant();
 			ImageFormat i = extension switch
 			{
 				".BMP" => ImageFormat.Bmp,

src/BizHawk.Client.EmuHawk/MainForm.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.Drawing;
 using System.Drawing.Imaging;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -1109,7 +1110,7 @@ namespace BizHawk.Client.EmuHawk
 					{
 						if (ie.LogicalButton.Button.Length == 1)
 						{
-							var c = ie.LogicalButton.Button.ToLower()[0];
+							var c = ie.LogicalButton.Button.ToLowerInvariant()[0];
 							if ((c >= 'a' && c <= 'z') || c == ' ')
 							{
 								SendAltKeyChar(c);
@@ -1308,7 +1309,7 @@ namespace BizHawk.Client.EmuHawk
 			using (var bb = Config.ScreenshotCaptureOsd ? CaptureOSD() : MakeScreenshotImage())
 			{
 				using var img = bb.ToSysdrawingBitmap();
-				if (Path.GetExtension(path).ToUpper() == ".JPG")
+				if (Path.GetExtension(path).ToUpperInvariant() == ".JPG")
 				{
 					img.Save(fi.FullName, ImageFormat.Jpeg);
 				}
@@ -2448,7 +2449,8 @@ namespace BizHawk.Client.EmuHawk
 				BindingFlags.NonPublic | BindingFlags.InvokeMethod | BindingFlags.Instance,
 				null,
 				MainformMenu,
-				new object/*?*/[] { c });
+				new object/*?*/[] { c },
+				CultureInfo.InvariantCulture);
 
 		public static readonly FilesystemFilterSet ConfigFileFSFilterSet = new(new FilesystemFilter("Config File", new[] { "ini" }))
 		{

src/BizHawk.Client.EmuHawk/PlatformChooser.cs

@@ -32,7 +32,7 @@ namespace BizHawk.Client.EmuHawk
 				? $"{RomGame.RomData.Length / 1024 / 1024:n0}mb"
 				: $"{RomGame.RomData.Length / 1024:n0}kb";
 
-			ExtensionLabel.Text = RomGame.Extension.ToLower();
+			ExtensionLabel.Text = RomGame.Extension.ToLowerInvariant();
 			HashBox.Text = RomGame.GameInfo.Hash;
 			int count = 0;
 			int spacing = 25;
@@ -67,7 +67,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (AlwaysCheckbox.Checked)
 			{
-				_config.PreferredPlatformsForExtensions[RomGame.Extension.ToLower()] = PlatformChoice;
+				_config.PreferredPlatformsForExtensions[RomGame.Extension.ToLowerInvariant()] = PlatformChoice;
 			}
 
 			Close();

src/BizHawk.Client.EmuHawk/RetroAchievements/RAIntegration.Update.cs

@@ -7,6 +7,7 @@ using Newtonsoft.Json;
 using BizHawk.BizInvoke;
 using BizHawk.Common;
 using BizHawk.Client.Common;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Client.EmuHawk
 {
@@ -46,7 +47,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private static bool DownloadDll(string url)
 		{
-			if (url.StartsWith("http:"))
+			if (url.StartsWithOrdinal("http:"))
 			{
 				// force https
 				url = url.Replace("http:", "https:");

src/BizHawk.Client.EmuHawk/RetroAchievements/RetroAchievements.GameVerification.cs

@@ -108,7 +108,7 @@ namespace BizHawk.Client.EmuHawk
 							exePath = Encoding.ASCII.GetString(buf2048);
 
 							// "BOOT = cdrom:" precedes the path
-							var index = exePath.IndexOf("BOOT = cdrom:");
+							var index = exePath.IndexOf("BOOT = cdrom:", StringComparison.Ordinal);
 							if (index < -1) break;
 							exePath = exePath.Remove(0, index + 13);
 

src/BizHawk.Client.EmuHawk/config/FirmwaresConfig.cs

@@ -113,7 +113,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				var lva = (ListViewItem)a;
 				var lvb = (ListViewItem)b;
-				return Sign * string.Compare(lva.SubItems[Column].Text, lvb.SubItems[Column].Text);
+				return Sign * string.CompareOrdinal(lva.SubItems[Column].Text, lvb.SubItems[Column].Text);
 			}
 		}
 

src/BizHawk.Client.EmuHawk/config/HotkeyConfig.cs

@@ -203,7 +203,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (e.IsPressed(Keys.Enter) || e.IsPressed(Keys.Tab))
 			{
-				var k = HotkeyInfo.AllHotkeys.FirstOrNull(kvp => string.Compare(kvp.Value.DisplayName, SearchBox.Text, true) is 0)?.Key;
+				var k = HotkeyInfo.AllHotkeys.FirstOrNull(kvp => string.Compare(kvp.Value.DisplayName, SearchBox.Text, StringComparison.OrdinalIgnoreCase) is 0)?.Key;
 
 				// Found
 				if (k is not null)

src/BizHawk.Client.EmuHawk/movie/PlayMovie.cs

@@ -210,7 +210,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				foreach (var ext in MovieService.MovieExtensions)
 				{
-					if ($".{ext}".Equals(Path.GetExtension(_movieList[indices[i]].Filename), StringComparison.InvariantCultureIgnoreCase))
+					if ($".{ext}".Equals(Path.GetExtension(_movieList[indices[i]].Filename), StringComparison.OrdinalIgnoreCase))
 					{
 						tas.Add(i);
 					}

src/BizHawk.Client.EmuHawk/tools/Debugger/BreakpointControl.cs

@@ -6,6 +6,7 @@ using System.Windows.Forms;
 using BizHawk.Client.Common;
 using BizHawk.Client.EmuHawk.Properties;
 using BizHawk.Common.NumberExtensions;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.EmuHawk
@@ -64,7 +65,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			BreakpointCallback(addr, value, flags);
 
-			var seekBreakpoint = _breakpoints.FirstOrDefault(x => x.Name.StartsWith(SeekName));
+			var seekBreakpoint = _breakpoints.FirstOrDefault(x => x.Name.StartsWithOrdinal(SeekName));
 
 			if (seekBreakpoint != null)
 			{
@@ -166,7 +167,7 @@ namespace BizHawk.Client.EmuHawk
 
 		public void RemoveCurrentSeek()
 		{
-			var seekBreakpoint = _breakpoints.FirstOrDefault(x => x.Name.StartsWith(SeekName));
+			var seekBreakpoint = _breakpoints.FirstOrDefault(x => x.Name.StartsWithOrdinal(SeekName));
 
 			if (seekBreakpoint != null)
 			{

src/BizHawk.Client.EmuHawk/tools/GameShark.cs

@@ -44,7 +44,7 @@ namespace BizHawk.Client.EmuHawk
 			{
 				try
 				{
-					var code = l.ToUpper().Trim();
+					var code = l.ToUpperInvariant().Trim();
 					var decoder = new GameSharkDecoder(MemoryDomains, Emulator.SystemId);
 					var result = decoder.Decode(code);
 					var domain = decoder.CheatDomain();
@@ -82,4 +82,4 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 	}
-}
+}

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

@@ -281,7 +281,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			long found = -1;
 
-			var search = value.Replace(" ", "").ToUpper();
+			var search = value.Replace(" ", "").ToUpperInvariant();
 			if (string.IsNullOrEmpty(search))
 			{
 				return;
@@ -341,7 +341,7 @@ namespace BizHawk.Client.EmuHawk
 		{
 			long found = -1;
 
-			var search = value.Replace(" ", "").ToUpper();
+			var search = value.Replace(" ", "").ToUpperInvariant();
 			if (string.IsNullOrEmpty(search))
 			{
 				return;

src/BizHawk.Client.EmuHawk/tools/Lua/Libraries/FormsLuaLibrary.cs

@@ -1456,7 +1456,7 @@ namespace BizHawk.Client.EmuHawk
 			textbox.Multiline = multiline;
 			if (scrollbars != null)
 			{
-				switch (scrollbars.ToUpper())
+				switch (scrollbars.ToUpperInvariant())
 				{
 					case "VERTICAL":
 						textbox.ScrollBars = ScrollBars.Vertical;
@@ -1489,7 +1489,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (boxtype != null)
 			{
-				switch (boxtype.ToUpper())
+				switch (boxtype.ToUpperInvariant())
 				{
 					case "HEX":
 					case "HEXADECIMAL":

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

@@ -14,6 +14,7 @@ using BizHawk.Client.EmuHawk.ToolExtensions;
 using BizHawk.Common;
 using BizHawk.Common.CollectionExtensions;
 using BizHawk.Common.PathExtensions;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.EmuHawk
@@ -446,7 +447,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private string DressUpRelative(string path)
 		{
-			return path.StartsWith(".\\") ? path.Replace(".\\", "") : path;
+			return path.StartsWithOrdinal(".\\") ? path.Replace(".\\", "") : path;
 		}
 
 		private void UpdateNumberOfScripts()
@@ -1267,12 +1268,12 @@ namespace BizHawk.Client.EmuHawk
 			{
 				foreach (var path in filePaths)
 				{
-					if (Path.GetExtension(path)?.ToLower() == ".lua" || Path.GetExtension(path)?.ToLower() == ".txt")
+					if (Path.GetExtension(path)?.ToLowerInvariant() == ".lua" || Path.GetExtension(path)?.ToLowerInvariant() == ".txt")
 					{
 						LoadLuaFile(path);
 						UpdateDialog();
 					}
-					else if (Path.GetExtension(path)?.ToLower() == ".luases")
+					else if (Path.GetExtension(path)?.ToLowerInvariant() == ".luases")
 					{
 						LoadLuaSession(path);
 						return;

src/BizHawk.Client.EmuHawk/tools/Lua/LuaPictureBox.cs

@@ -283,7 +283,7 @@ namespace BizHawk.Client.EmuHawk
 			var fStyle = FontStyle.Regular;
 			if (fontStyle != null)
 			{
-				switch (fontStyle.ToLower())
+				switch (fontStyle.ToLowerInvariant())
 				{
 					default:
 					case "regular":
@@ -311,7 +311,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (horizAlign != null)
 			{
-				switch (horizAlign.ToLower())
+				switch (horizAlign.ToLowerInvariant())
 				{
 					default:
 					case "left":
@@ -328,7 +328,7 @@ namespace BizHawk.Client.EmuHawk
 
 			if (vertAlign != null)
 			{
-				switch (vertAlign.ToLower())
+				switch (vertAlign.ToLowerInvariant())
 				{
 					default:
 					case "top":

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

@@ -62,7 +62,7 @@ namespace BizHawk.Client.EmuHawk
 			AddButton_Click(null, null);
 			AddButton_Click(null, null);
 
-			if (!Game.IsNullInstance() && !MainForm.CurrentlyOpenRom.EndsWith(".xml"))
+			if (!Game.IsNullInstance() && !MainForm.CurrentlyOpenRom.EndsWithOrdinal(".xml"))
 			{
 				if (MainForm.CurrentlyOpenRom.Contains("|"))
 				{

src/BizHawk.Client.EmuHawk/tools/TAStudio/TAStudio.MenuItems.cs

@@ -99,12 +99,12 @@ namespace BizHawk.Client.EmuHawk
 		public bool LoadMovieFile(string filename, bool askToSave = true)
 		{
 			if (askToSave && !AskSaveChanges()) return false;
-			if (filename.EndsWith(MovieService.TasMovieExtension))
+			if (filename.EndsWithOrdinal(MovieService.TasMovieExtension))
 			{
 				LoadFileWithFallback(filename);
 				return true; //TODO should this return false if it fell back to a new project?
 			}
-			if (filename.EndsWith(MovieService.StandardMovieExtension))
+			if (filename.EndsWithOrdinal(MovieService.StandardMovieExtension))
 			{
 				if (!DialogController.ShowMessageBox2(
 					caption: "Convert movie",
@@ -1209,7 +1209,7 @@ namespace BizHawk.Client.EmuHawk
 			int workingHeight = Screen.FromControl(this).WorkingArea.Height;
 			int rowHeight = ColumnsSubMenu.Height + 4;
 			int maxRows = workingHeight / rowHeight;
-			int keyCount = columns.Count(c => c.Name.StartsWith("Key "));
+			int keyCount = columns.Count(c => c.Name.StartsWithOrdinal("Key "));
 			int keysMenusCount = (int)Math.Ceiling((double)keyCount / maxRows);
 
 			var keysMenus = new ToolStripMenuItem[keysMenusCount];
@@ -1248,7 +1248,7 @@ namespace BizHawk.Client.EmuHawk
 					((ToolStripMenuItem)sender.OwnerItem).ShowDropDown();
 				};
 
-				if (column.Name.StartsWith("Key "))
+				if (column.Name.StartsWithOrdinal("Key "))
 				{
 					keysMenus
 						.First(m => m.DropDownItems.Count < maxRows)

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

@@ -9,6 +9,7 @@ using BizHawk.Client.Common;
 using BizHawk.Client.EmuHawk.ToolExtensions;
 using BizHawk.Client.EmuHawk.Properties;
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores.Nintendo.N64;
 
@@ -383,29 +384,29 @@ namespace BizHawk.Client.EmuHawk
 					|| c.Name == "Light Sensor"
 					|| c.Name == "Disc Select"
 					|| c.Name == "Disk Index"
-					|| c.Name.StartsWith("Tilt")
-					|| c.Name.StartsWith("Key ")
-					|| c.Name.StartsWith("Open")
-					|| c.Name.StartsWith("Close")
-					|| c.Name.EndsWith("Tape")
-					|| c.Name.EndsWith("Disk")
-					|| c.Name.EndsWith("Block")
-					|| c.Name.EndsWith("Status"));
+					|| c.Name.StartsWithOrdinal("Tilt")
+					|| c.Name.StartsWithOrdinal("Key ")
+					|| c.Name.StartsWithOrdinal("Open")
+					|| c.Name.StartsWithOrdinal("Close")
+					|| c.Name.EndsWithOrdinal("Tape")
+					|| c.Name.EndsWithOrdinal("Disk")
+					|| c.Name.EndsWithOrdinal("Block")
+					|| c.Name.EndsWithOrdinal("Status"));
 
 			if (Emulator.SystemId is VSystemID.Raw.N64)
 			{
 				foreach (var c in TasView.AllColumns
-					.Where(static c => c.Name.EndsWith(" C Up") || c.Name.EndsWith(" C Down")
-						|| c.Name.EndsWith(" C Left") || c.Name.EndsWith(" C Right")))
+					.Where(static c => c.Name.EndsWithOrdinal(" C Up") || c.Name.EndsWithOrdinal(" C Down")
+						|| c.Name.EndsWithOrdinal(" C Left") || c.Name.EndsWithOrdinal(" C Right")))
 				{
 					c.Text = $"c{c.Text.ToUpperInvariant()}"; // prepend 'c' to differentiate from L/R buttons -- only affects table header
 				}
 				var fakeAnalogControls = TasView.AllColumns
 					.Where(c =>
-						c.Name.EndsWith("A Up")
-						|| c.Name.EndsWith("A Down")
-						|| c.Name.EndsWith("A Left")
-						|| c.Name.EndsWith("A Right"));
+						c.Name.EndsWithOrdinal("A Up")
+						|| c.Name.EndsWithOrdinal("A Down")
+						|| c.Name.EndsWithOrdinal("A Left")
+						|| c.Name.EndsWithOrdinal("A Right"));
 
 				columnsToHide = columnsToHide.Concat(fakeAnalogControls);
 			}

src/BizHawk.Common/Extensions/PathExtensions.cs

@@ -14,14 +14,14 @@ namespace BizHawk.Common.PathExtensions
 		public static bool IsSubfolderOf(this string? childPath, string? parentPath)
 		{
 			if (childPath == null || parentPath == null) return false;
-			if (childPath == parentPath || childPath.StartsWith($"{parentPath}{Path.DirectorySeparatorChar}")) return true;
+			if (childPath == parentPath || childPath.StartsWithOrdinal($"{parentPath}{Path.DirectorySeparatorChar}")) return true;
 
 			if (OSTailoredCode.IsUnixHost)
 			{
 #if true
 				var c = OSTailoredCode.SimpleSubshell("realpath", $"-Lm \"{childPath}\"", $"invalid path {childPath} or missing realpath binary");
 				var p = OSTailoredCode.SimpleSubshell("realpath", $"-Lm \"{parentPath}\"", $"invalid path {parentPath} or missing realpath binary");
-				return c == p || c.StartsWith($"{p}/");
+				return c == p || c.StartsWithOrdinal($"{p}/");
 #else // written for Unix port but may be useful for Windows when moving to .NET Core
 				var parentUriPath = new Uri(parentPath.TrimEnd('.')).AbsolutePath.TrimEnd('/');
 				try
@@ -72,7 +72,7 @@ namespace BizHawk.Common.PathExtensions
 			if (OSTailoredCode.IsUnixHost)
 			{
 				var realpathOutput = OSTailoredCode.SimpleSubshell("realpath", $"--relative-to=\"{fromPath}\" \"{toPath}\"", $"invalid path {toPath}, invalid path {fromPath}, or missing realpath binary");
-				return !realpathOutput.StartsWith("../") && realpathOutput != "." && realpathOutput != ".." ? $"./{realpathOutput}" : realpathOutput;
+				return !realpathOutput.StartsWithOrdinal("../") && realpathOutput != "." && realpathOutput != ".." ? $"./{realpathOutput}" : realpathOutput;
 			}
 
 			//TODO merge this with the Windows implementation in MakeRelativeTo
@@ -97,14 +97,14 @@ namespace BizHawk.Common.PathExtensions
 		{
 			if (path.IsAbsolute())
 				return path;
-			else
-			{
-				// FileInfo for normalisation ("C:\a\b\..\c" => "C:\a\c")
-				var mycwd = cwd ?? (OSTailoredCode.IsUnixHost ? Environment.CurrentDirectory : CWDHacks.Get());
-				var finalpath = $"{mycwd}/{path}";
-				var fi = new FileInfo(finalpath);
-				return fi.FullName;
-			}
+			else
+			{
+				// FileInfo for normalisation ("C:\a\b\..\c" => "C:\a\c")
+				var mycwd = cwd ?? (OSTailoredCode.IsUnixHost ? Environment.CurrentDirectory : CWDHacks.Get());
+				var finalpath = $"{mycwd}/{path}";
+				var fi = new FileInfo(finalpath);
+				return fi.FullName;
+			}
 		}
 
 		/// <returns>the absolute path equivalent to <paramref name="path"/> which contains <c>%exe%</c> (expanded) as a prefix</returns>
@@ -126,7 +126,7 @@ namespace BizHawk.Common.PathExtensions
 			if (!OSTailoredCode.IsUnixHost) return absolutePath.Replace(basePath, ".").RemoveSuffix(Path.DirectorySeparatorChar);
 #if true // Unix implementation using realpath
 			var realpathOutput = OSTailoredCode.SimpleSubshell("realpath", $"--relative-base=\"{basePath}\" \"{absolutePath}\"", $"invalid path {absolutePath}, invalid path {basePath}, or missing realpath binary");
-			return !realpathOutput.StartsWith("../") && realpathOutput != "." && realpathOutput != ".." ? $"./{realpathOutput}" : realpathOutput;
+			return !realpathOutput.StartsWithOrdinal("../") && realpathOutput != "." && realpathOutput != ".." ? $"./{realpathOutput}" : realpathOutput;
 #else // for some reason there were two Unix implementations in the codebase before me? --yoshi
 			// alt. #1
 			if (!IsSubfolder(basePath, absolutePath)) return OSTailoredCode.IsUnixHost && basePath.TrimEnd('.') == $"{absolutePath}/" ? "." : absolutePath;

src/BizHawk.Common/Extensions/StringExtensions.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.CompilerServices;
 
@@ -20,7 +21,7 @@ namespace BizHawk.Common.StringExtensions
 		/// <see langword="true"/> if <paramref name="str"/> appears in <paramref name="options"/> (case-insensitive)
 		/// </returns>
 		public static bool In(this string str, params string[] options) =>
-			options.Any(opt => string.Equals(opt, str, StringComparison.InvariantCultureIgnoreCase));
+			options.Any(opt => string.Equals(opt, str, StringComparison.OrdinalIgnoreCase));
 
 		/// <returns>
 		/// <paramref name="str"/> with the first char removed, or
@@ -88,7 +89,7 @@ namespace BizHawk.Common.StringExtensions
 		/// </returns>
 		public static string SubstringAfter(this string str, string delimiter, string notFoundValue)
 		{
-			var index = str.IndexOf(delimiter);
+			var index = str.IndexOf(delimiter, StringComparison.Ordinal);
 			return index < 0 ? notFoundValue : str.Substring(index + delimiter.Length, str.Length - index - delimiter.Length);
 		}
 
@@ -147,7 +148,7 @@ namespace BizHawk.Common.StringExtensions
 		/// </returns>
 		public static string? SubstringBeforeOrNull(this string str, string delimiter)
 		{
-			var index = str.IndexOf(delimiter);
+			var index = str.IndexOf(delimiter, StringComparison.Ordinal);
 			return index < 0 ? null : str.Substring(0, index);
 		}
 
@@ -165,5 +166,9 @@ namespace BizHawk.Common.StringExtensions
 		/// <remarks><c>"abc,def,ghi".TransformFields(',', s => s.Reverse()) == "cba,fed,ihg"</c></remarks>
 		public static string TransformFields(this string str, char delimiter, Func<string, string> transform)
 			=> string.Join(delimiter.ToString(), str.Split(delimiter).Select(transform));
+
+		public static bool StartsWithOrdinal(this string str, string value) => str.StartsWith(value, StringComparison.Ordinal);
+
+		public static bool EndsWithOrdinal(this string str, string value) => str.EndsWith(value, StringComparison.Ordinal);
 	}
 }

src/BizHawk.Common/HawkFile/HawkFile.cs

@@ -142,7 +142,7 @@ namespace BizHawk.Common
 					}
 					for (int i = 0, l = scanResults.Count; i < l; i++)
 					{
-						if (string.Equals(scanResults[i].Name, autobind, StringComparison.InvariantCultureIgnoreCase))
+						if (string.Equals(scanResults[i].Name, autobind, StringComparison.OrdinalIgnoreCase))
 						{
 							BindArchiveMember(i);
 							return;

src/BizHawk.Common/PropertyGridConverters/DescribableEnumConverter.cs

@@ -26,7 +26,7 @@ namespace BizHawk.Common
 			return Enum.Parse(
 				enumType,
 				enumType.GetFields(BindingFlags.Public | BindingFlags.Static)
-					.FirstOrDefault(fi => valueStr.Equals((fi.GetCustomAttribute(typeof(DisplayAttribute)) as DisplayAttribute)?.Name))?.Name
+					.FirstOrDefault(fi => valueStr.Equals((fi.GetCustomAttribute(typeof(DisplayAttribute)) as DisplayAttribute)?.Name, StringComparison.Ordinal))?.Name
 					?? valueStr
 			);
 		}

src/BizHawk.Common/TempFileManager.cs

@@ -34,7 +34,7 @@ namespace BizHawk.Common
 		{
 			var (dir, filename) = path.SplitPathToDirAndFile();
 			_ = dir ?? throw new InvalidOperationException();
-			if (!filename.StartsWith("biz-"))
+			if (!filename.StartsWith("biz-", StringComparison.Ordinal))
 			{
 				throw new InvalidOperationException();
 			}
@@ -128,4 +128,4 @@ namespace BizHawk.Common
 			Environment.SetEnvironmentVariable("TEMP", path);
 		}
 	}
-}
+}

src/BizHawk.Common/Util.cs

@@ -108,7 +108,7 @@ namespace BizHawk.Common
 		/// <returns>all <see cref="Type">Types</see> with the name <paramref name="className"/></returns>
 		/// <remarks>adapted from https://stackoverflow.com/a/13727044/7467292</remarks>
 		public static IList<Type> GetTypeByName(string className) => AppDomain.CurrentDomain.GetAssemblies()
-			.SelectMany(asm => asm.GetTypesWithoutLoadErrors().Where(type => className.Equals(type.Name, StringComparison.InvariantCultureIgnoreCase))).ToList();
+			.SelectMany(asm => asm.GetTypesWithoutLoadErrors().Where(type => className.Equals(type.Name, StringComparison.OrdinalIgnoreCase))).ToList();
 
 		/// <remarks>TODO replace this with GetTypes (i.e. the try block) when VB.NET dep is properly removed</remarks>
 		public static IEnumerable<Type> GetTypesWithoutLoadErrors(this Assembly assembly)

src/BizHawk.Emulation.Common/Base Implementations/ControllerDefinition.cs

@@ -8,6 +8,7 @@ using System.Text.RegularExpressions;
 
 using BizHawk.Common;
 using BizHawk.Common.CollectionExtensions;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Common
 {
@@ -147,7 +148,7 @@ namespace BizHawk.Emulation.Common
 				}
 
 				// Hack for things like gameboy/ti-83 as opposed to genesis with no controllers plugged in
-				return allNames.Exists(static b => b.StartsWith("Up")) ? 1 : 0;
+				return allNames.Exists(static b => b.StartsWithOrdinal("Up")) ? 1 : 0;
 			}
 		}
 

src/BizHawk.Emulation.Common/Base Implementations/LinkedDebuggable.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Common
 {
@@ -37,7 +38,7 @@ namespace BizHawk.Emulation.Common
 		{
 			for (int i = 0; i < _numCores; i++)
 			{
-				if (register.StartsWith($"P{i + 1} "))
+				if (register.StartsWithOrdinal($"P{i + 1} "))
 				{
 					_linkedCores[i].AsDebuggable().SetCpuRegister(register.Replace($"P{i + 1} ", ""), value);
 				}

src/BizHawk.Emulation.Common/DSKIdentifier.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Common
 {
@@ -40,7 +41,7 @@ namespace BizHawk.Emulation.Common
 
 		private void ParseDskImage()
 		{
-			string ident = Encoding.ASCII.GetString(_data, 0, 16).ToUpper();
+			string ident = Encoding.ASCII.GetString(_data, 0, 16).ToUpperInvariant();
 			if (ident.Contains("MV - CPC"))
 			{
 				ParseDsk();
@@ -81,8 +82,8 @@ namespace BizHawk.Emulation.Common
 					if (s.SectorData == null || s.SectorData.Length == 0)
 						continue;
 
-					string str = Encoding.ASCII.GetString(s.SectorData, 0, s.SectorData.Length).ToUpper();
-					if (str.Contains("PLUS3DOS"))
+					string str = Encoding.ASCII.GetString(s.SectorData, 0, s.SectorData.Length);
+					if (str.Contains("PLUS3DOS", StringComparison.OrdinalIgnoreCase))
 					{
 						IdentifiedSystem = VSystemID.Raw.ZXSpectrum;
 						return;

src/BizHawk.Emulation.Common/Database/Database.cs

@@ -423,7 +423,7 @@ namespace BizHawk.Emulation.Common
 			// If filename is all-caps, then attempt to proper-case the title.
 			if (!string.IsNullOrWhiteSpace(game.Name) && game.Name == game.Name.ToUpperInvariant())
 			{
-				game.Name = Thread.CurrentThread.CurrentCulture.TextInfo.ToTitleCase(game.Name.ToLower());
+				game.Name = Thread.CurrentThread.CurrentCulture.TextInfo.ToTitleCase(game.Name.ToLowerInvariant());
 			}
 
 			return game;

src/BizHawk.Emulation.Cores/Arcades/MAME/MAME.cs

@@ -47,17 +47,17 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 					text + (text == "" ? "" : "\r\n") +
 					string.Join("\r\n", _romHashes.Select(static r => $"{r.Value} - {r.Key}"));
 
-				if (text.ToLower().Contains("imperfect"))
+				if (text.Contains("imperfect", StringComparison.OrdinalIgnoreCase))
 				{
 					lp.Game.Status = RomStatus.Imperfect;
 				}
 
-				if (text.ToLower().Contains("unemulated"))
+				if (text.Contains("unemulated", StringComparison.OrdinalIgnoreCase))
 				{
 					lp.Game.Status = RomStatus.Unimplemented;
 				}
 
-				if (text.ToLower().Contains("doesn't work"))
+				if (text.Contains("doesn't work", StringComparison.OrdinalIgnoreCase))
 				{
 					lp.Game.Status = RomStatus.NotWorking;
 				}
@@ -94,7 +94,7 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 			var hashes = string.Concat(_romHashes.Values
 				.Where(static s => s.Contains("SHA:"))
 				.Select(static s => s.Split(' ')
-				.First(static s => s.StartsWith("SHA:"))
+				.First(static s => s.StartsWithOrdinal("SHA:"))
 				.RemovePrefix("SHA:")));
 
 			lp.Game.Name = _gameFullName;

src/BizHawk.Emulation.Cores/CPUs/FairchildF8/F3850.Disassembler.cs

@@ -15,17 +15,17 @@ namespace BizHawk.Emulation.Cores.Components.FairchildF8
 			//n immediate succeeds the opcode and the displacement (if present)
 			//nn immediately succeeds the opcode and the displacement (if present)
 
-			if (format.IndexOf("nn") != -1)
+			if (format.IndexOf("nn", StringComparison.Ordinal) != -1)
 			{
 				format = format.Replace("nn", read(addr++)
 					.ToString("X2") + read(addr++)
 					.ToString("X2") + "h"); // MSB is read first
 			}
 
-			if (format.IndexOf("n") != -1) format = format.Replace("n", $"{read(addr++):X2}h");
+			if (format.IndexOf("n", StringComparison.Ordinal) != -1) format = format.Replace("n", $"{read(addr++):X2}h");
 
-			if (format.IndexOf("+d") != -1) format = format.Replace("+d", "d");
-			if (format.IndexOf("d") != -1)
+			if (format.IndexOf("+d", StringComparison.Ordinal) != -1) format = format.Replace("+d", "d");
+			if (format.IndexOf("d", StringComparison.Ordinal) != -1)
 			{
 				var b = unchecked((sbyte)read(addr++));
 				format = format.Replace("d", $"{(b < 0 ? '-' : '+')}{(b < 0 ? -b : b):X2}h");

src/BizHawk.Emulation.Cores/CPUs/FairchildF8/F3850.Registers.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 namespace BizHawk.Emulation.Cores.Components.FairchildF8
@@ -274,7 +275,7 @@ namespace BizHawk.Emulation.Cores.Components.FairchildF8
 
 		public void SetCpuRegister(string register, int value)
 		{
-			if (register.StartsWith("SPR"))
+			if (register.StartsWithOrdinal("SPR"))
 			{
 				var reg = Convert.ToInt32(register.Replace("SPR", ""));
 

src/BizHawk.Emulation.Cores/CPUs/HuC6280/Execute.cs

@@ -1,4 +1,5 @@
 using System;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 
 // Do not modify this file directly! This is GENERATED code.
@@ -2339,7 +2340,7 @@ namespace BizHawk.Emulation.Cores.Components.H6280
 					case 0xF4: // SET
 						int a; // TODO remove these extra checks
 						string b = Disassemble(PC, out a);
-						if (b.StartsWith("ADC") == false && b.StartsWith("EOR") == false && b.StartsWith("AND") == false && b.StartsWith("ORA") == false)
+						if (b.StartsWithOrdinal("ADC") == false && b.StartsWithOrdinal("EOR") == false && b.StartsWithOrdinal("AND") == false && b.StartsWithOrdinal("ORA") == false)
 							Console.WriteLine("SETTING T FLAG, NEXT INSTRUCTION IS UNHANDLED:  {0}", b);
 						FlagT = true;
 						PendingCycles -= 2;

src/BizHawk.Emulation.Cores/CPUs/Z80A/NewDisassembler.cs

@@ -13,11 +13,11 @@ namespace BizHawk.Emulation.Cores.Components.Z80A
 			//n immediate succeeds the opcode and the displacement (if present)
 			//nn immediately succeeds the opcode and the displacement (if present)
 
-			if (format.IndexOf("nn") != -1) format = format.Replace("nn", $"{read(addr++) + (read(addr++) << 8):X4}h"); // LSB is read first
-			if (format.IndexOf("n") != -1) format = format.Replace("n", $"{read(addr++):X2}h");
+			if (format.IndexOf("nn", StringComparison.Ordinal) != -1) format = format.Replace("nn", $"{read(addr++) + (read(addr++) << 8):X4}h"); // LSB is read first
+			if (format.IndexOf("n", StringComparison.Ordinal) != -1) format = format.Replace("n", $"{read(addr++):X2}h");
 
-			if (format.IndexOf("+d") != -1) format = format.Replace("+d", "d");
-			if (format.IndexOf("d") != -1)
+			if (format.IndexOf("+d", StringComparison.Ordinal) != -1) format = format.Replace("+d", "d");
+			if (format.IndexOf("d", StringComparison.Ordinal) != -1)
 			{
 				var b = unchecked ((sbyte) read(addr++));
 				format = format.Replace("d", $"{(b < 0 ? '-' : '+')}{(b < 0 ? -b : b):X2}h");

src/BizHawk.Emulation.Cores/Computers/AmstradCPC/Machine/CPCBase.Input.cs

@@ -1,4 +1,6 @@
-namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
+using BizHawk.Common.StringExtensions;
+
+namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 {
 	/// <summary>
 	/// The abstract class that all emulated models will inherit from
@@ -64,7 +66,7 @@
 				// non matrix keys (J2)
 				foreach (string k in KeyboardDevice.NonMatrixKeys)
 				{
-					if (!k.StartsWith("P2"))
+					if (!k.StartsWithOrdinal("P2"))
 						continue;
 
 					bool currState = CPC._controller.IsPressed(k);

src/BizHawk.Emulation.Cores/Computers/AmstradCPC/Machine/CPCBase.Media.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 {
@@ -232,7 +233,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 			string hdr = Encoding.ASCII.GetString(data.Take(16).ToArray());
 
 			// disk checking first
-			if (hdr.ToUpper().Contains("EXTENDED CPC DSK") || hdr.ToUpper().Contains("MV - CPC"))
+			if (hdr.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase) || hdr.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
 			{
 				// amstrad .dsk disk file
 				// check for number of sides
@@ -244,7 +245,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 			}
 
 			// tape checking
-			if (hdr.ToUpper().StartsWith("ZXTAPE!"))
+			if (hdr.StartsWith("ZXTAPE!", StringComparison.OrdinalIgnoreCase))
 			{
 				// cdt tape file
 				return CPCMediaType.Tape;
@@ -263,4 +264,3 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 		DiskDoubleSided
 	}
 }
-

src/BizHawk.Emulation.Cores/Computers/AmstradCPC/Media/Disk/CPCExtendedFloppyDisk.cs

@@ -2,6 +2,7 @@
 using BizHawk.Common;
 using System;
 using System.Collections.Generic;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 {
@@ -27,7 +28,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
 
-			if (!ident.ToUpper().Contains("EXTENDED CPC DSK"))
+			if (!ident.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;
@@ -152,7 +153,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 		{
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
-			if (!ident.ToUpper().Contains("EXTENDED CPC DSK"))
+			if (!ident.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/AmstradCPC/Media/Disk/CPCFloppyDisk.cs

@@ -2,6 +2,7 @@
 using BizHawk.Common;
 using System.Collections.Generic;
 using System;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 {
@@ -27,7 +28,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
 
-			if (!ident.ToUpper().Contains("MV - CPC"))
+			if (!ident.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;
@@ -158,7 +159,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 		{
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
-			if (!ident.ToUpper().Contains("MV - CPC"))
+			if (!ident.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/AmstradCPC/Media/Disk/FloppyDisk.cs

@@ -3,6 +3,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 {
@@ -235,7 +236,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
 			// check for SPEEDLOCK ident in sector 0
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[0].SectorData, 0, DiskTracks[0].Sectors[0].SectorData.Length);
-			if (!ident.ToUpper().Contains("SPEEDLOCK"))
+			if (!ident.Contains("SPEEDLOCK", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// check for correct sector 0 lengths
@@ -297,7 +298,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
 			// check for ALKATRAZ ident in sector 0
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[0].SectorData, 0, DiskTracks[0].Sectors[0].SectorData.Length);
-			if (!ident.ToUpper().Contains("ALKATRAZ PROTECTION SYSTEM"))
+			if (!ident.Contains("ALKATRAZ PROTECTION SYSTEM", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// ALKATRAZ NOTES (-asni 2018-05-01)
@@ -338,7 +339,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
 			// check for PAUL OWENS ident in sector 2
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[2].SectorData, 0, DiskTracks[0].Sectors[2].SectorData.Length);
-			if (!ident.ToUpper().Contains("PAUL OWENS"))
+			if (!ident.Contains("PAUL OWENS", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// Paul Owens Disk Protection Notes (-asni 2018-05-01)
@@ -380,7 +381,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
 			// check for Hexagon ident in sector 8
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[8].SectorData, 0, DiskTracks[0].Sectors[8].SectorData.Length);
-			if (ident.ToUpper().Contains("GON DISK PROT"))
+			if (ident.Contains("GON DISK PROT", StringComparison.OrdinalIgnoreCase))
 				return true;
 
 			// hexagon protection may not be labelled as such

src/BizHawk.Emulation.Cores/Computers/Commodore64/C64FormatFinder.cs

@@ -1,5 +1,6 @@
 using System.IO;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.Commodore64
 {
@@ -12,37 +13,36 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64
 				return C64Format.Unknown;
 			}
 
-			using (var mem = new MemoryStream(data))
+			using (var reader = new BinaryReader(new MemoryStream(data)))
 			{
-				var reader = new BinaryReader(mem);
 				var header = Encoding.GetEncoding(437).GetString(reader.ReadBytes(0x10));
 
-				if (header.StartsWith("C64 CARTRIDGE   "))
+				if (header.StartsWithOrdinal("C64 CARTRIDGE   "))
 				{
 					return C64Format.CRT;
 				}
 
-				if (header.StartsWith("GCR-1541"))
+				if (header.StartsWithOrdinal("GCR-1541"))
 				{
 					return C64Format.G64;
 				}
 
-				if (header.StartsWith("C64S tape image ") || header.StartsWith("C64 tape image f"))
+				if (header.StartsWithOrdinal("C64S tape image ") || header.StartsWithOrdinal("C64 tape image f"))
 				{
 					return C64Format.T64;
 				}
 
-				if (header.StartsWith("C64-TAPE-RAW"))
+				if (header.StartsWithOrdinal("C64-TAPE-RAW"))
 				{
 					return C64Format.TAP;
 				}
 
-				if (header.StartsWith("C64File"))
+				if (header.StartsWithOrdinal("C64File"))
 				{
 					return C64Format.P00; // poo :)
 				}
 
-				if (header.StartsWith("P64-1541"))
+				if (header.StartsWithOrdinal("P64-1541"))
 				{
 					return C64Format.P64;
 				}

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Machine/SpectrumBase.Input.cs

@@ -1,5 +1,6 @@
 using System.Collections.Generic;
 using System.Linq;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -66,7 +67,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 				// non matrix keys
 				foreach (string k in KeyboardDevice.NonMatrixKeys)
 				{
-					if (!k.StartsWith("Key"))
+					if (!k.StartsWithOrdinal("Key"))
 						continue;
 
 					bool currState = Spectrum._controller.IsPressed(k);
@@ -337,4 +338,3 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 		}
 	}
 }
-

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Machine/SpectrumBase.Media.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -245,7 +246,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
             string hdr = Encoding.ASCII.GetString(data.Take(16).ToArray());
 
 			// disk checking first
-			if (hdr.ToUpper().Contains("EXTENDED CPC DSK") || hdr.ToUpper().Contains("MV - CPC"))
+			if (hdr.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase) || hdr.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .dsk disk file
                 // check for number of sides
@@ -255,20 +256,20 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
                 else
                     return SpectrumMediaType.DiskDoubleSided;
             }
-			if (hdr.ToUpper().StartsWith("FDI"))
+			if (hdr.StartsWith("FDI", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .fdi disk file
                 return SpectrumMediaType.Disk;
             }
-            if (hdr.ToUpper().StartsWith("CAPS"))
+            if (hdr.StartsWith("CAPS", StringComparison.OrdinalIgnoreCase))
             {
                 // IPF format file
                 return SpectrumMediaType.Disk;
             }
-            if (hdr.ToUpper().StartsWith("UDI!") && data[0x08] == 0)
+            if (hdr.StartsWith("UDI!", StringComparison.OrdinalIgnoreCase) && data[0x08] == 0)
             {
                 // UDI v1.0
-                if (hdr.StartsWith("udi!"))
+                if (hdr.StartsWithOrdinal("udi!"))
                 {
                     throw new NotSupportedException("ZXHawk currently does not supported UDIv1.0 with compression.");
                 }
@@ -282,22 +283,22 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
             }
 
             // tape checking
-            if (hdr.ToUpper().StartsWith("ZXTAPE!"))
+            if (hdr.StartsWith("ZXTAPE!", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .tzx tape file
                 return SpectrumMediaType.Tape;
             }
-            if (hdr.ToUpper().StartsWith("PZXT"))
+            if (hdr.StartsWith("PZXT", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .tzx tape file
                 return SpectrumMediaType.Tape;
             }
-            if (hdr.ToUpper().StartsWith("COMPRESSED SQ"))
+            if (hdr.StartsWith("COMPRESSED SQ", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .tzx tape file
                 return SpectrumMediaType.Tape;
             }
-            if (hdr.ToUpper().Contains("WAVE"))
+            if (hdr.Contains("WAVE", StringComparison.OrdinalIgnoreCase))
             {
                 // spectrum .tzx tape file
                 return SpectrumMediaType.Tape;

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/CPCFormat/CPCExtendedFloppyDisk.cs

@@ -2,6 +2,7 @@
 using BizHawk.Common;
 using System;
 using System.Collections.Generic;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -27,7 +28,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
 
-			if (!ident.ToUpper().Contains("EXTENDED CPC DSK"))
+			if (!ident.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;
@@ -163,7 +164,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 		{
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
-			if (!ident.ToUpper().Contains("EXTENDED CPC DSK"))
+			if (!ident.Contains("EXTENDED CPC DSK", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/CPCFormat/CPCFloppyDisk.cs

@@ -2,6 +2,7 @@
 using BizHawk.Common;
 using System;
 using System.Collections.Generic;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -27,7 +28,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
 
-			if (!ident.ToUpper().Contains("MV - CPC"))
+			if (!ident.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;
@@ -168,7 +169,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 		{
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
-			if (!ident.ToUpper().Contains("MV - CPC"))
+			if (!ident.Contains("MV - CPC", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/FloppyDisk.cs

@@ -3,6 +3,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -235,7 +236,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 			// check for SPEEDLOCK ident in sector 0
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[0].SectorData, 0, DiskTracks[0].Sectors[0].SectorData.Length);
-			if (!ident.ToUpper().Contains("SPEEDLOCK"))
+			if (!ident.Contains("SPEEDLOCK", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// check for correct sector 0 lengths
@@ -297,7 +298,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 			// check for ALKATRAZ ident in sector 0
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[0].SectorData, 0, DiskTracks[0].Sectors[0].SectorData.Length);
-			if (!ident.ToUpper().Contains("ALKATRAZ PROTECTION SYSTEM"))
+			if (!ident.Contains("ALKATRAZ PROTECTION SYSTEM", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// ALKATRAZ NOTES (-asni 2018-05-01)
@@ -338,7 +339,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 			// check for PAUL OWENS ident in sector 2
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[2].SectorData, 0, DiskTracks[0].Sectors[2].SectorData.Length);
-			if (!ident.ToUpper().Contains("PAUL OWENS"))
+			if (!ident.Contains("PAUL OWENS", StringComparison.OrdinalIgnoreCase))
 				return false;
 
 			// Paul Owens Disk Protection Notes (-asni 2018-05-01)
@@ -380,7 +381,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 			// check for Hexagon ident in sector 8
 			string ident = Encoding.ASCII.GetString(DiskTracks[0].Sectors[8].SectorData, 0, DiskTracks[0].Sectors[8].SectorData.Length);
-			if (ident.ToUpper().Contains("GON DISK PROT"))
+			if (ident.Contains("GON DISK PROT", StringComparison.OrdinalIgnoreCase))
 				return true;
 
 			// hexagon protection may not be labelled as such

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/IPFFormat/IPFFloppyDisk.cs

@@ -4,6 +4,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -26,7 +27,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 16);
 
-			if (!ident.ToUpper().Contains("CAPS"))
+			if (!ident.Contains("CAPS", StringComparison.OrdinalIgnoreCase))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Disk/UDIFormat/UDI1_0FloppyDisk.cs

@@ -4,6 +4,7 @@ using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using BizHawk.Common.StringExtensions;
 
 namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 {
@@ -26,7 +27,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 4);
 
-			if (!ident.StartsWith("UDI!") && !ident.StartsWith("udi!"))
+			if (!ident.StartsWithOrdinal("UDI!") && !ident.StartsWithOrdinal("udi!"))
 			{
 				// incorrect format
 				return false;
@@ -83,7 +84,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// look for standard magic string
 			string ident = Encoding.ASCII.GetString(data, 0, 4);
 
-			if (!ident.StartsWith("UDI!") && !ident.StartsWith("udi!"))
+			if (!ident.StartsWithOrdinal("UDI!") && !ident.StartsWithOrdinal("udi!"))
 			{
 				// incorrect format
 				return false;

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Tape/CSW/CswConverter.cs

@@ -57,7 +57,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			int majorVer = data[8];
 			int minorVer = data[9];
 
-			if (ident.ToUpper() != "COMPRESSED SQUARE WAVE")
+			if (ident.ToUpperInvariant() != "COMPRESSED SQUARE WAVE")
 			{
 				// this is not a valid CSW format file
 				return false;
@@ -80,7 +80,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// (first 22 bytes of the file)
 			string ident = Encoding.ASCII.GetString(data, 0, 22);
 
-			if (ident.ToUpper() != "COMPRESSED SQUARE WAVE")
+			if (ident.ToUpperInvariant() != "COMPRESSED SQUARE WAVE")
 			{
 				// this is not a valid CSW format file
 				throw new Exception($"{nameof(CswConverter)}: This is not a valid CSW format file");

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Tape/PZX/PzxConverter.cs

@@ -67,7 +67,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			int majorVer = data[8];
 			int minorVer = data[9];
 
-			if (ident.ToUpper() != "PZXT")
+			if (ident.ToUpperInvariant() != "PZXT")
 			{
 				// this is not a valid PZX format file
 				return false;
@@ -96,7 +96,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// check whether this is a valid pzx format file by looking at the identifier in the header block
 			string ident = Encoding.ASCII.GetString(data, 0, 4);
 
-			if (ident.ToUpper() != "PZXT")
+			if (ident.ToUpperInvariant() != "PZXT")
 			{
 				// this is not a valid TZX format file
 				throw new Exception($"{nameof(PzxConverter)}: This is not a valid PZX format file");

src/BizHawk.Emulation.Cores/Computers/SinclairSpectrum/Media/Tape/WAV/WavConverter.cs

@@ -52,7 +52,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// check whether this is a valid wav format file by looking at the identifier in the header
 			string ident = Encoding.ASCII.GetString(data, 8, 4);
 
-			if (ident.ToUpper() != "WAVE")
+			if (ident.ToUpperInvariant() != "WAVE")
 			{
 				// this is not a valid WAV format file
 				return false;
@@ -74,7 +74,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 			// check whether this is a valid pzx format file by looking at the identifier in the header block
 			string ident = Encoding.ASCII.GetString(data, 8, 4);
 
-			if (ident.ToUpper() != "WAVE")
+			if (ident.ToUpperInvariant() != "WAVE")
 			{
 				// this is not a valid TZX format file
 				throw new Exception($"{nameof(WavConverter)}: This is not a valid WAV format file");

src/BizHawk.Emulation.Cores/Computers/TIC80/TIC80.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Collections.ObjectModel;
 
 using BizHawk.Common;
+using BizHawk.Common.StringExtensions;
 using BizHawk.Emulation.Common;
 using BizHawk.Emulation.Cores.Waterbox;
 
@@ -119,7 +120,7 @@ namespace BizHawk.Emulation.Cores.Computers.TIC80
 
 				foreach (var n in ret.BoolButtons)
 				{
-					if (n.StartsWith("Mouse"))
+					if (n.StartsWithOrdinal("Mouse"))
 					{
 						ret.CategoryLabels[n] = "Mouse";
 					}
@@ -127,7 +128,7 @@ namespace BizHawk.Emulation.Cores.Computers.TIC80
 
 				foreach (var n in ret.Axes.Keys)
 				{
-					if (n.StartsWith("Mouse"))
+					if (n.StartsWithOrdinal("Mouse"))
 					{
 						ret.CategoryLabels[n] = "Mouse";
 					}