Revert "fix: Address CA1847 rule"

This reverts commit 2f8273ae64.

src/Avalonia.Base/AvaloniaProperty.cs

@@ -12,12 +12,6 @@ namespace Avalonia
     /// </summary>
     public abstract class AvaloniaProperty : IEquatable<AvaloniaProperty>, IPropertyInfo
     {
-#if NET6_0_OR_GREATER
-        internal const char Period = '.';
-#else
-        internal const string Period = ".";
-#endif
-
         /// <summary>
         /// Represents an unset property value.
         /// </summary>
@@ -47,7 +41,7 @@ namespace Avalonia
         {
             _ = name ?? throw new ArgumentNullException(nameof(name));
 
-            if (name.Contains(Period))
+            if (name.Contains("."))
             {
                 throw new ArgumentException("'name' may not contain periods.");
             }

src/Avalonia.Base/AvaloniaPropertyRegistry.cs

@@ -228,7 +228,7 @@ namespace Avalonia
             _ = type ?? throw new ArgumentNullException(nameof(type));
             _ = name ?? throw new ArgumentNullException(nameof(name));
 
-            if (name.Contains(AvaloniaProperty.Period))
+            if (name.Contains("."))
             {
                 throw new InvalidOperationException("Attached properties not supported.");
             }

src/Avalonia.Base/Media/UnicodeRange.cs

@@ -104,11 +104,6 @@ namespace Avalonia.Media
 
     public readonly struct UnicodeRangeSegment
     {
-#if NET6_0_OR_GREATER
-        private const char Question = '?';
-#else
-        private const string Question = "?";
-#endif
         private static Regex s_regex = new Regex(@"^(?:[uU]\+)?(?:([0-9a-fA-F](?:[0-9a-fA-F?]{1,5})?))$");
 
         public UnicodeRangeSegment(int start, int end)
@@ -168,7 +163,7 @@ namespace Avalonia.Media
                             throw new FormatException("Could not parse specified Unicode range segment.");
                         }
 
-                        if (!single.Value.Contains(Question))
+                        if (!single.Value.Contains("?"))
                         {
                             start = int.Parse(single.Groups[1].Value, System.Globalization.NumberStyles.HexNumber);
                             end = start;

src/Avalonia.Controls/Flyouts/FlyoutBase.cs

@@ -597,7 +597,7 @@ namespace Avalonia.Controls.Primitives
             for (int i = presenter.Classes.Count - 1; i >= 0; i--)
             {
                 if (!classes.Contains(presenter.Classes[i]) &&
-                    !presenter.Classes[i].Contains(':'))
+                    !presenter.Classes[i].Contains(":"))
                 {
                     presenter.Classes.RemoveAt(i);
                 }

src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs

@@ -1151,8 +1151,8 @@ namespace Avalonia.Controls
             if (PIndex >= 0)
             {
                 //stringToTest contains a "P" between 2 "'", it's considered as text, not percent
-                var isText = stringToTest.Substring(0, PIndex).Contains('\'')
-                             && stringToTest.Substring(PIndex, FormatString.Length - PIndex).Contains('\'');
+                var isText = stringToTest.Substring(0, PIndex).Contains("'")
+                             && stringToTest.Substring(PIndex, FormatString.Length - PIndex).Contains("'");
 
                 return !isText;
             }

src/Avalonia.Remote.Protocol/MetsysBson.cs

@@ -1364,13 +1364,13 @@ namespace Metsys.Bson
             var optionsString = ReadName();
 
             var options = RegexOptions.None;
-            if (optionsString.Contains('e')) options = options | RegexOptions.ECMAScript;
-            if (optionsString.Contains('i')) options = options | RegexOptions.IgnoreCase;
-            if (optionsString.Contains('l')) options = options | RegexOptions.CultureInvariant;
-            if (optionsString.Contains('m')) options = options | RegexOptions.Multiline;
-            if (optionsString.Contains('s')) options = options | RegexOptions.Singleline;
-            if (optionsString.Contains('w')) options = options | RegexOptions.IgnorePatternWhitespace;
-            if (optionsString.Contains('x')) options = options | RegexOptions.ExplicitCapture;
+            if (optionsString.Contains("e")) options = options | RegexOptions.ECMAScript;
+            if (optionsString.Contains("i")) options = options | RegexOptions.IgnoreCase;
+            if (optionsString.Contains("l")) options = options | RegexOptions.CultureInvariant;
+            if (optionsString.Contains("m")) options = options | RegexOptions.Multiline;
+            if (optionsString.Contains("s")) options = options | RegexOptions.Singleline;
+            if (optionsString.Contains("w")) options = options | RegexOptions.IgnorePatternWhitespace;
+            if (optionsString.Contains("x")) options = options | RegexOptions.ExplicitCapture;
 
             return new Regex(pattern, options);
         }

src/Markup/Avalonia.Markup.Xaml.Loader/CompilerExtensions/AvaloniaXamlIlLanguageParseIntrinsics.cs

@@ -14,12 +14,6 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions
 {
     class AvaloniaXamlIlLanguageParseIntrinsics
     {
-#if NET6_0_OR_GREATER
-        private const string Colon = ":";
-#else
-        private const string Colon = ":";
-#endif
-
         public static bool TryConvert(AstTransformationContext context, IXamlAstValueNode node, string text, IXamlType type, AvaloniaXamlIlWellKnownTypes types, out IXamlAstValueNode result)
         {
             if (type.FullName == "System.TimeSpan")
@@ -29,7 +23,7 @@ namespace Avalonia.Markup.Xaml.XamlIl.CompilerExtensions
                 if (!TimeSpan.TryParse(tsText, CultureInfo.InvariantCulture, out var timeSpan))
                 {
                     // // shorthand seconds format (ie. "0.25")
-                    if (!tsText.Contains(Colon) && double.TryParse(tsText,
+                    if (!tsText.Contains(":") && double.TryParse(tsText,
                         NumberStyles.Float | NumberStyles.AllowThousands,
                         CultureInfo.InvariantCulture, out var seconds))
                         timeSpan = TimeSpan.FromSeconds(seconds);

src/Markup/Avalonia.Markup.Xaml/Converters/TimeSpanTypeConverter.cs

@@ -7,12 +7,6 @@ namespace Avalonia.Markup.Xaml.Converters
 
     public class TimeSpanTypeConverter : System.ComponentModel.TimeSpanConverter
     {
-#if NET6_0_OR_GREATER
-        private const char Colon = ':';
-#else
-        private const string Colon = ":";
-#endif
-
         public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
         {
             return base.CanConvertFrom(context, sourceType);
@@ -21,7 +15,7 @@ namespace Avalonia.Markup.Xaml.Converters
         public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
         {
             var valueStr = (string)value;
-            if (!valueStr.Contains(Colon))
+            if (!valueStr.Contains(":"))
             {
                 // shorthand seconds format (ie. "0.25")
                 var secs = double.Parse(valueStr, CultureInfo.InvariantCulture);
@@ -31,4 +25,4 @@ namespace Avalonia.Markup.Xaml.Converters
             return base.ConvertFrom(context, culture, value);
         }
     }
-}
+}