[core] use StringComparison.Ordinal everywhere (#4988)

Context: https://docs.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1307
Context: https://docs.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1309
Context: dotnet/runtime#43956

I was reviewing `dotnet trace` output of the .NET Podcast app:

    6.32ms Microsoft.Maui.Controls!Microsoft.Maui.Controls.ShellNavigationManager.GetNavigationState
    3.82ms Microsoft.Maui.Controls!Microsoft.Maui.Controls.ShellUriHandler.FormatUri

The bulk of this time is spent in `string.StartsWith()`, doing a
culture-aware string comparison?

    3.82ms System.Private.CoreLib!System.String.StartsWith
    2.57ms System.Private.CoreLib!System.Globalization.CultureInfo.get_CurrentCulture

This looks to be showing the cost of the 1st culture-aware comparision
plus any time making these slower string comparisons. It would be
ideal if project templates did not even hit
`CultureInfo.get_CurrentCulture`.

To solve this, let's add to the `.editorconfig` file:

    dotnet_diagnostic.CA1307.severity = error
    dotnet_diagnostic.CA1309.severity = error

And then fix all the places errors appear.

There are some complications in projects that use `netstandard2.0`:

1. For `Contains()` use `IndexOf()` instead.

2. Use `#if NETSTANDARD2_0` for `GetHashCode()` or `Replace()`. Use the `char` overload
of `string.Replace()` where possible.

3. Generally, `InvariantCulture` should not be used.

After these changes, the `FormatUri` method disappears completely from
the trace, and we instead get:

    2.88ms Microsoft.Maui.Controls!Microsoft.Maui.Controls.ShellNavigationManager.GetNavigationState

I suspect this saves ~3.44ms for any MAUI app startup, and a small
amount more depending on the number of string comparisions happening.

.editorconfig

@@ -23,6 +23,10 @@ indent_style = tab
 # https://docs.microsoft.com/en-us/dotnet/fundamentals/code-analysis/quality-rules/ca1416
 dotnet_diagnostic.CA1416.severity = none
 
+# Code analyzers
+dotnet_diagnostic.CA1307.severity = error
+dotnet_diagnostic.CA1309.severity = error
+
 # Modifier preferences
 dotnet_style_require_accessibility_modifiers = never:suggestion
 

src/BlazorWebView/src/Maui/Windows/WinUIWebViewManager.cs

@@ -91,7 +91,7 @@ protected override async Task HandleWebResourceRequest(CoreWebView2WebResourceRe
 					{
 						relativePath = _hostPageRelativePath;
 					}
-					relativePath = Path.Combine(_contentRootDir, relativePath.Replace("/", "\\"));
+					relativePath = Path.Combine(_contentRootDir, relativePath.Replace('/', '\\'));
 
 					var winUIItem = await Package.Current.InstalledLocation.TryGetItemAsync(relativePath);
 					if (winUIItem != null)

src/BlazorWebView/src/SharedSource/QueryStringHelper.cs

@@ -3,6 +3,8 @@
 
 #nullable enable
 
+using System;
+
 namespace Microsoft.AspNetCore.Components.WebView
 {
 	internal static class QueryStringHelper
@@ -13,7 +15,7 @@ public static string RemovePossibleQueryString(string? url)
 			{
 				return string.Empty;
 			}
-			var indexOfQueryString = url.IndexOf('?');
+			var indexOfQueryString = url.IndexOf('?', StringComparison.Ordinal);
 			return (indexOfQueryString == -1)
 				? url
 				: url.Substring(0, indexOfQueryString);

src/Compatibility/ControlGallery/src/Android/TestCloudService.cs

@@ -1,3 +1,4 @@
+using System;
 using Microsoft.Maui.Controls.Compatibility.ControlGallery;
 
 namespace Microsoft.Maui.Controls.Compatibility.ControlGallery.Android
@@ -8,7 +9,7 @@ public bool IsOnTestCloud()
 		{
 			var isInTestCloud = System.Environment.GetEnvironmentVariable("XAMARIN_TEST_CLOUD");
 
-			return isInTestCloud != null && isInTestCloud.Equals("1");
+			return isInTestCloud != null && isInTestCloud.Equals("1", StringComparison.Ordinal);
 		}
 
 		public string GetTestCloudDeviceName()

src/Compatibility/ControlGallery/src/Core/GalleryPages/CollectionViewGalleries/DemoFilteredItemSource.cs

@@ -40,7 +40,7 @@ public DemoFilteredItemSource(int count = 50, Func<string, CollectionViewGallery
 		private bool ItemMatches(string filter, CollectionViewGalleryTestItem item)
 		{
 			filter = filter ?? "";
-			return item.Caption.ToLower().Contains(filter?.ToLower());
+			return item.Caption.IndexOf(filter, StringComparison.OrdinalIgnoreCase) != -1;
 		}
 
 		public void FilterItems(string filter)

src/Compatibility/ControlGallery/src/UITests.Shared/Utilities/ParsingUtils.cs

@@ -15,7 +15,7 @@ public static Font ParseUIFont(string font)
 
 			// Logger.LogLine ("TEST PARSING");
 
-			if (font.Contains("font-weight: bold;"))
+			if (font.IndexOf("font-weight: bold;", StringComparison.Ordinal) != -1)
 			{
 				// Logger.LogLine ("Found Bold");
 				fontAttrs = FontAttributes.Bold;

src/Compatibility/ControlGallery/src/WinUI/WinUIStartup.cs

@@ -26,7 +26,7 @@ public static MauiApp CreateMauiApp()
 				.AddWindows(windows => windows
 					.OnLaunching((_, e) =>
 					{
-						if (!string.IsNullOrWhiteSpace(e.Arguments) && e.Arguments.Contains("RunningAsUITests"))
+						if (!string.IsNullOrWhiteSpace(e.Arguments) && e.Arguments.Contains("RunningAsUITests", StringComparison.Ordinal))
 						{
 							App.RunningAsUITests = true;
 							ControlGallery.App.PreloadTestCasesIssuesList = false;

src/Compatibility/ControlGallery/src/iOS/AppDelegate.cs

@@ -89,7 +89,7 @@ public bool IsOnTestCloud()
 		{
 			var isInTestCloud = Environment.GetEnvironmentVariable("XAMARIN_TEST_CLOUD");
 
-			return isInTestCloud != null && isInTestCloud.Equals("1");
+			return isInTestCloud != null && isInTestCloud.Equals("1", StringComparison.Ordinal);
 		}
 
 		public string GetTestCloudDeviceName()

src/Compatibility/Core/src/Android/BorderBackgroundManager.cs

@@ -219,17 +219,17 @@ void BorderElementPropertyChanged(object sender, PropertyChangedEventArgs e)
 				return;
 			}
 
-			if (e.PropertyName.Equals(Button.BorderColorProperty.PropertyName) ||
-				e.PropertyName.Equals(Button.BorderWidthProperty.PropertyName) ||
-				e.PropertyName.Equals(Button.CornerRadiusProperty.PropertyName) ||
-				e.PropertyName.Equals(VisualElement.BackgroundColorProperty.PropertyName) ||
-				e.PropertyName.Equals(VisualElement.BackgroundProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.Button.UseDefaultPaddingProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.Button.UseDefaultShadowProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.ImageButton.IsShadowEnabledProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.ImageButton.ShadowColorProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.ImageButton.ShadowOffsetProperty.PropertyName) ||
-				e.PropertyName.Equals(Specifics.ImageButton.ShadowRadiusProperty.PropertyName))
+			if (e.PropertyName.Equals(Button.BorderColorProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Button.BorderWidthProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Button.CornerRadiusProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(VisualElement.BackgroundColorProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(VisualElement.BackgroundProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.Button.UseDefaultPaddingProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.Button.UseDefaultShadowProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.ImageButton.IsShadowEnabledProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.ImageButton.ShadowColorProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.ImageButton.ShadowOffsetProperty.PropertyName, StringComparison.Ordinal) ||
+				e.PropertyName.Equals(Specifics.ImageButton.ShadowRadiusProperty.PropertyName, StringComparison.Ordinal))
 			{
 				Reset();
 				UpdateDrawable();

src/Compatibility/Core/src/Android/Renderers/DatePickerRenderer.cs

@@ -160,7 +160,7 @@ void SetDate(DateTime date)
 			{
 				EditText.Text = date.ToShortDateString();
 			}
-			else if (Element.Format.Contains('/'))
+			else if (Element.Format.Contains('/', StringComparison.Ordinal))
 			{
 				EditText.Text = date.ToString(Element.Format, CultureInfo.InvariantCulture);
 			}

src/Compatibility/Core/src/Android/Renderers/TimePickerRenderer.cs

@@ -20,7 +20,7 @@ public abstract class TimePickerRendererBase<TControl> : ViewRenderer<TimePicker
 		[PortHandler]
 		bool Is24HourView
 		{
-			get => (DateFormat.Is24HourFormat(Context) && Element.Format == (string)TimePicker.FormatProperty.DefaultValue) || Element.Format?.Contains('H') == true;
+			get => (DateFormat.Is24HourFormat(Context) && Element.Format == (string)TimePicker.FormatProperty.DefaultValue) || Element.Format?.Contains('H', StringComparison.Ordinal) == true;
 		}
 
 		public TimePickerRendererBase(Context context) : base(context)

src/Compatibility/Core/src/Android/ResourceManager.cs

@@ -405,7 +405,7 @@ static int IdFromTitle(string title, [DynamicallyAccessedMembers(DynamicallyAcce
 
 			// When searching by reflection you would use a "_" instead of a "."
 			// So this accounts for cases where users were searching with an "_"
-			if ((id = SearchByIdentifier(name.Replace("_", "."), defType, resource, packageName)) > 0)
+			if ((id = SearchByIdentifier(name.Replace("_", ".", StringComparison.Ordinal), defType, resource, packageName)) > 0)
 				return id;
 
 			int SearchByIdentifier(string n, string d, Resources r, string p)

src/Compatibility/Core/src/Windows/DatePickerRenderer.cs

@@ -143,7 +143,7 @@ void OnControlDateChanged(object sender, DatePickerValueChangedEventArgs e)
 
 		bool CheckDateFormat()
 		{
-			return String.IsNullOrWhiteSpace(Element.Format) || Element.Format.Equals("d");
+			return String.IsNullOrWhiteSpace(Element.Format) || Element.Format.Equals("d", StringComparison.Ordinal);
 		}
 
 		[PortHandler]
@@ -165,7 +165,7 @@ void UpdateMonth()
 			{
 				Control.MonthFormat = "month";
 			}
-			else if (Element.Format.Equals("D"))
+			else if (Element.Format.Equals("D", StringComparison.Ordinal))
 			{
 				Control.MonthFormat = "month.full";
 			}
@@ -191,7 +191,7 @@ void UpdateDay()
 			{
 				Control.DayFormat = "day";
 			}
-			else if (Element.Format.Equals("D"))
+			else if (Element.Format.Equals("D", StringComparison.Ordinal))
 			{
 				Control.DayFormat = "dayofweek.full";
 			}
@@ -217,7 +217,7 @@ void UpdateYear()
 			{
 				Control.YearFormat = "year";
 			}
-			else if (Element.Format.Equals("D"))
+			else if (Element.Format.Equals("D", StringComparison.Ordinal))
 			{
 				Control.YearFormat = "year.full";
 			}

src/Compatibility/Core/src/Windows/FileImageSourceHandler.cs

@@ -70,7 +70,7 @@ void UpdateImageDirectory(FileImageSource fileSource)
 
 				var directory = IOPath.GetDirectoryName(filePath);
 
-				if (string.IsNullOrEmpty(directory) || !IOPath.GetFullPath(directory).Equals(IOPath.GetFullPath(imageDirectory)))
+				if (string.IsNullOrEmpty(directory) || !IOPath.GetFullPath(directory).Equals(IOPath.GetFullPath(imageDirectory), StringComparison.Ordinal))
 				{
 					filePath = IOPath.Combine(imageDirectory, filePath);
 					fileSource.File = filePath;

src/Compatibility/Core/src/Windows/FontImageSourceHandler.cs

@@ -124,7 +124,7 @@ string GetFontSource(FontImageSource fontImageSource)
 
 				foreach(var family in allFamilies)
 				{
-					if(family.Contains(source))
+					if(family.Contains(source, StringComparison.Ordinal))
 					{
 						fontSource = family;
 						break;

src/Compatibility/Core/src/Windows/TimePickerRenderer.cs

@@ -168,7 +168,7 @@ void UpdateFont()
 		void UpdateTime()
 		{
 			Control.Time = Element.Time;
-			if (Element.Format?.Contains('H') == true)
+			if (Element.Format?.Contains('H', StringComparison.Ordinal) == true)
 			{
 				Control.ClockIdentifier = "24HourClock";
 			}

src/Compatibility/Core/src/Windows/WebViewRenderer.cs

@@ -52,7 +52,7 @@ public void LoadHtml(string html, string baseUrl)
 			_internalWebView.NavigationCompleted += async (sender, args) =>
 			{
 				// Generate a version of the <base> script with the correct <base> tag
-				var script = BaseInsertionScript.Replace("baseTag", baseTag);
+				var script = BaseInsertionScript.Replace("baseTag", baseTag, StringComparison.Ordinal);
 
 				// Run it and retrieve the updated HTML from our WebView
 				await sender.ExecuteScriptAsync(script);

src/Compatibility/Core/src/iOS/NativeViewPropertyListener.cs

@@ -22,7 +22,7 @@ public NativeViewPropertyListener(string targetProperty)
 
 		public override void ObserveValue(NSString keyPath, NSObject ofObject, NSDictionary change, IntPtr context)
 		{
-			if (keyPath.ToString().Equals(TargetProperty, StringComparison.InvariantCultureIgnoreCase))
+			if (keyPath.ToString().Equals(TargetProperty, StringComparison.OrdinalIgnoreCase))
 				PropertyChanged?.Invoke(ofObject, new PropertyChangedEventArgs(TargetProperty));
 			else
 				base.ObserveValue(keyPath, ofObject, change, context);

src/Compatibility/Core/src/iOS/Renderers/DatePickerRenderer.cs

@@ -176,12 +176,12 @@ void UpdateDateFromModel(bool animate)
 				_picker.SetDate(Element.Date.ToNSDate(), animate);
 
 			// Can't use Element.Format because it won't display the correct format if the region and language are set differently
-			if (string.IsNullOrWhiteSpace(Element.Format) || Element.Format.Equals("d") || Element.Format.Equals("D"))
+			if (string.IsNullOrWhiteSpace(Element.Format) || Element.Format.Equals("d", StringComparison.OrdinalIgnoreCase))
 			{
 				NSDateFormatter dateFormatter = new NSDateFormatter();
 				dateFormatter.TimeZone = NSTimeZone.FromGMT(0);
 
-				if (Element.Format?.Equals("D") == true)
+				if (Element.Format?.Equals("D", StringComparison.Ordinal) == true)
 				{
 					dateFormatter.DateStyle = NSDateFormatterStyle.Long;
 					var strDate = dateFormatter.StringFor(_picker.Date);
@@ -194,7 +194,7 @@ void UpdateDateFromModel(bool animate)
 					Control.Text = strDate;
 				}
 			}
-			else if (Element.Format.Contains("/"))
+			else if (Element.Format.Contains('/', StringComparison.Ordinal))
 			{
 				Control.Text = Element.Date.ToString(Element.Format, CultureInfo.InvariantCulture);
 			}

src/Compatibility/Core/src/iOS/Renderers/TimePickerRenderer.cs

@@ -233,13 +233,13 @@ void UpdateTime()
 				Control.Text = DateTime.Today.Add(Element.Time).ToString(Element.Format, cultureInfos);
 			}
 
-			if (Element.Format?.Contains('H') == true)
+			if (Element.Format?.Contains('H', StringComparison.Ordinal) == true)
 			{
 				var ci = new System.Globalization.CultureInfo("de-DE");
 				NSLocale locale = new NSLocale(ci.TwoLetterISOLanguageName);
 				_picker.Locale = locale;
 			}
-			else if (Element.Format?.Contains('h') == true)
+			else if (Element.Format?.Contains('h', StringComparison.Ordinal) == true)
 			{
 				var ci = new System.Globalization.CultureInfo("en-US");
 				NSLocale locale = new NSLocale(ci.TwoLetterISOLanguageName);

src/Compatibility/Core/src/iOS/Renderers/WkWebViewRenderer.cs

@@ -365,7 +365,7 @@ async Task<List<NSHttpCookie>> GetCookiesFromNativeStore(string url)
 			{
 				// we don't care that much about this being accurate
 				// the cookie container will split the cookies up more correctly
-				if (!cookie.Domain.Contains(domain) && !domain.Contains(cookie.Domain))
+				if (!cookie.Domain.Contains(domain, StringComparison.Ordinal) && !domain.Contains(cookie.Domain, StringComparison.Ordinal))
 					continue;
 
 				existingCookies.Add(cookie);
@@ -563,7 +563,7 @@ async Task DeleteCookies(List<NSHttpCookie> cookies)
 
 						foreach (var deleteme in cookies)
 						{
-							if (record.DisplayName.Contains(deleteme.Domain) || deleteme.Domain.Contains(record.DisplayName))
+							if (record.DisplayName.Contains(deleteme.Domain, StringComparison.Ordinal) || deleteme.Domain.Contains(record.DisplayName, StringComparison.Ordinal))
 							{
 								WKWebsiteDataStore.DefaultDataStore.RemoveDataOfTypes(record.DataTypes,
 									  new[] { record }, () => { });

src/Controls/Maps/src/Pin.cs

@@ -70,10 +70,17 @@ public override int GetHashCode()
 		{
 			unchecked
 			{
+#if NETSTANDARD2_0
 				int hashCode = Label?.GetHashCode() ?? 0;
 				hashCode = (hashCode * 397) ^ Position.GetHashCode();
 				hashCode = (hashCode * 397) ^ (int)Type;
 				hashCode = (hashCode * 397) ^ (Address?.GetHashCode() ?? 0);
+#else
+				int hashCode = Label?.GetHashCode(StringComparison.Ordinal) ?? 0;
+				hashCode = (hashCode * 397) ^ Position.GetHashCode();
+				hashCode = (hashCode * 397) ^ (int)Type;
+				hashCode = (hashCode * 397) ^ (Address?.GetHashCode(StringComparison.Ordinal) ?? 0);
+#endif
 				return hashCode;
 			}
 		}
@@ -106,7 +113,9 @@ public bool SendInfoWindowClick()
 
 		bool Equals(Pin other)
 		{
-			return string.Equals(Label, other.Label) && Equals(Position, other.Position) && Type == other.Type && string.Equals(Address, other.Address);
+			return string.Equals(Label, other.Label, StringComparison.Ordinal) &&
+				Equals(Position, other.Position) && Type == other.Type &&
+				string.Equals(Address, other.Address, StringComparison.Ordinal);
 		}
 	}
 }

src/Controls/samples/Controls.Sample/Pages/Controls/CollectionViewGalleries/DataTemplateSelectorGallery.xaml.cs

@@ -36,7 +36,7 @@ private bool ItemMatches(string filter, CollectionViewGalleryTestItem item)
 				return true;
 			}
 
-			return item.Date.DayOfWeek.ToString().ToLower().Contains(filter.ToLower());
+			return item.Date.DayOfWeek.ToString().Contains(filter, StringComparison.OrdinalIgnoreCase);
 		}
 	}
 

src/Controls/samples/Controls.Sample/Pages/Controls/CollectionViewGalleries/DemoFilteredItemSource.cs

@@ -40,7 +40,7 @@ public DemoFilteredItemSource(int count = 50, Func<string, CollectionViewGallery
 		private bool ItemMatches(string filter, CollectionViewGalleryTestItem item)
 		{
 			filter = filter ?? "";
-			return item.Caption.ToLower().Contains(filter?.ToLower());
+			return item.Caption.Contains(filter, StringComparison.OrdinalIgnoreCase);
 		}
 
 		public void FilterItems(string filter)

src/Controls/src/Core/Accelerator.cs

@@ -49,7 +49,11 @@ public static Accelerator FromString(string text)
 						case "fn":
 						case "win":
 							modifiers.Add(modiferMaskLower);
+#if NETSTANDARD2_0
 							text = text.Replace(modifierMask, "");
+#else
+							text = text.Replace(modifierMask, "", StringComparison.Ordinal);
+#endif
 							break;
 					}
 				}
@@ -89,7 +93,11 @@ bool Equals(Accelerator other)
 		/// <include file="../../docs/Microsoft.Maui.Controls/Accelerator.xml" path="//Member[@MemberName='GetHashCode']/Docs" />
 		public override int GetHashCode()
 		{
-			return ToString().GetHashCode();
+#if NETSTANDARD2_0
+			return _text.GetHashCode();
+#else
+			return _text.GetHashCode(StringComparison.Ordinal);
+#endif
 		}
 
 		public static implicit operator Accelerator(string accelerator)

src/Controls/src/Core/AnimatableKey.cs

@@ -47,18 +47,25 @@ public override int GetHashCode()
 			unchecked
 			{
 				IAnimatable target;
+#if NETSTANDARD2_0
 				if (!Animatable.TryGetTarget(out target))
 				{
 					return Handle?.GetHashCode() ?? 0;
 				}
-
 				return ((target?.GetHashCode() ?? 0) * 397) ^ (Handle?.GetHashCode() ?? 0);
+#else
+				if (!Animatable.TryGetTarget(out target))
+				{
+					return Handle?.GetHashCode(StringComparison.Ordinal) ?? 0;
+				}
+				return ((target?.GetHashCode() ?? 0) * 397) ^ (Handle?.GetHashCode(StringComparison.Ordinal) ?? 0);
+#endif
 			}
 		}
 
 		protected bool Equals(AnimatableKey other)
 		{
-			if (!string.Equals(Handle, other.Handle))
+			if (!string.Equals(Handle, other.Handle, StringComparison.Ordinal))
 			{
 				return false;
 			}

src/Controls/src/Core/BindablePropertyConverter.cs

@@ -81,7 +81,7 @@ public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo c
 
 			if (string.IsNullOrWhiteSpace(strValue))
 				return null;
-			if (strValue.Contains(":"))
+			if (strValue.IndexOf(":", StringComparison.Ordinal) != -1)
 			{
 				Application.Current?.FindMauiContext()?.CreateLogger<BindablePropertyConverter>()?.LogWarning("Can't resolve properties with xml namespace prefix.");
 				return null;