Use params and char overload

src/Microsoft.DotNet.Wpf/src/PresentationBuildTasks/MS/Internal/MarkupCompiler/MarkupCompiler.cs

@@ -1477,7 +1477,7 @@ internal string GetGenericTypeName(string typeName, string typeArgs)
             StringBuilder sb = new StringBuilder(typeName, 20);
             sb.Append(GENERIC_DELIMITER);
 
-            _typeArgsList = typeArgs.Split(new Char[] { COMMA });
+            _typeArgsList = typeArgs.Split(COMMA);
 
             sb.Append(_typeArgsList.Length);
 
@@ -1537,7 +1537,7 @@ private bool IsValidCLRNamespace(string ns, bool shouldThrow)
         {
             if (ns.Length > 0)
             {
-                string[] nsParts = ns.Split(new char[] { DOTCHAR });
+                string[] nsParts = ns.Split(DOTCHAR);
 
                 foreach (string nsPart in nsParts)
                 {
@@ -1629,7 +1629,7 @@ private string ParentFolderPrefix
                     {
                         string relPath = TargetPath.Substring(SourceFileInfo.SourcePath.Length);
                         relPath += SourceFileInfo.RelativeSourceFilePath;
-                        string[] dirs = relPath.Split(new Char[] { Path.DirectorySeparatorChar });
+                        string[] dirs = relPath.Split(Path.DirectorySeparatorChar);
                         for (int i = 1; i < dirs.Length; i++)
                         {
                             parentFolderPrefix += PARENTFOLDER;

src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Media/Animation/RepeatBehaviorConverter.cs

@@ -21,7 +21,7 @@ public sealed class RepeatBehaviorConverter : TypeConverter
     {
         #region Data
 
-        private static char[] _iterationCharacter = new char[] { 'x' };
+        private const char _iterationCharacter = 'x';
 
         #endregion
 
@@ -81,7 +81,7 @@ public override object ConvertFrom(
                     return RepeatBehavior.Forever;
                 }
                 else if (   stringValue.Length > 0
-                         && stringValue[stringValue.Length - 1] == _iterationCharacter[0])
+                         && stringValue[stringValue.Length - 1] == _iterationCharacter)
                 {
                     string stringDoubleValue = stringValue.TrimEnd(_iterationCharacter);
 

src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Media/Parsers.cs

@@ -105,7 +105,7 @@ static private Color ParseContextColor(string trimmedColor, IFormatProvider form
 
             string tokens = trimmedColor.Substring(s_ContextColor.Length);
             tokens = tokens.Trim();
-            string[] preSplit = tokens.Split(new Char[] { ' ' });
+            string[] preSplit = tokens.Split(' ');
             if (preSplit.GetLength(0)< 2)
             {
                 throw new FormatException(SR.Get(SRID.Parsers_IllegalToken));

src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Navigation/BaseUriHelper.cs

@@ -285,7 +285,7 @@ internal static void GetAssemblyNameAndPart(Uri uri, out string partName, out st
 
             if (fHasComponent)
             {
-                string[] assemblyInfo = firstSegment.Split(new char[] { COMPONENT_DELIMITER });
+                string[] assemblyInfo = firstSegment.Split(COMPONENT_DELIMITER);
 
                 int count = assemblyInfo.Length;
 
@@ -336,7 +336,7 @@ static internal bool IsComponentEntryAssembly(string component)
         {
             if (component.EndsWith(COMPONENT, StringComparison.OrdinalIgnoreCase))
             {
-                string[] assemblyInfo = component.Split(new Char[] { COMPONENT_DELIMITER });
+                string[] assemblyInfo = component.Split(COMPONENT_DELIMITER);
                 // Check whether the assembly name is the same as the EntryAssembly.
                 int count = assemblyInfo.Length;
                 if ((count >= 2) && (count <= 4))

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Annotations/Anchoring/FixedTextSelectionProcessor.cs

@@ -222,20 +222,20 @@ public override IList<ContentLocatorPart>
                     string value = "";
                     if (!double.IsNaN(fp.Segments[i].Start.X))
                     {
-                        value += fp.Segments[i].Start.X.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator[0] + fp.Segments[i].Start.Y.ToString(NumberFormatInfo.InvariantInfo);
+                        value += fp.Segments[i].Start.X.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator + fp.Segments[i].Start.Y.ToString(NumberFormatInfo.InvariantInfo);
                     }
                     else
                     {
-                        value += TextSelectionProcessor.Separator[0];
+                        value += TextSelectionProcessor.Separator;
                     }
-                    value += TextSelectionProcessor.Separator[0];
+                    value += TextSelectionProcessor.Separator;
                     if (!double.IsNaN(fp.Segments[i].End.X))
                     {
-                        value += fp.Segments[i].End.X.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator[0] + fp.Segments[i].End.Y.ToString(NumberFormatInfo.InvariantInfo);
+                        value += fp.Segments[i].End.X.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator + fp.Segments[i].End.Y.ToString(NumberFormatInfo.InvariantInfo);
                     }
                     else
                     {
-                        value += TextSelectionProcessor.Separator[0];
+                        value += TextSelectionProcessor.Separator;
                     }
 
                     part.NameValuePairs.Add(TextSelectionProcessor.SegmentAttribute + i.ToString(NumberFormatInfo.InvariantInfo), value);

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Annotations/Anchoring/TextSelectionProcessor.cs

@@ -169,7 +169,7 @@ public override IList<ContentLocatorPart>
             {
                 GetTextSegmentValues(textSegments[i], elementStart, elementEnd, out startOffset, out endOffset);
 
-                part.NameValuePairs.Add(SegmentAttribute + i.ToString(NumberFormatInfo.InvariantInfo), startOffset.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator[0] + endOffset.ToString(NumberFormatInfo.InvariantInfo));
+                part.NameValuePairs.Add(SegmentAttribute + i.ToString(NumberFormatInfo.InvariantInfo), startOffset.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator + endOffset.ToString(NumberFormatInfo.InvariantInfo));
             }
 
             part.NameValuePairs.Add(CountAttribute, textSegments.Count.ToString(NumberFormatInfo.InvariantInfo));
@@ -424,7 +424,7 @@ internal void SetTargetDocumentPageView(DocumentPageView target)
         internal const String IncludeOverlaps = "IncludeOverlaps";
 
         // Potential separators for values in segment name/value pairs
-        internal static readonly Char[] Separator = new Char[] { ',' };
+        internal const Char Separator = ',';
 
         // Name of locator part element
         internal static readonly XmlQualifiedName CharacterRangeElementName = new XmlQualifiedName("CharacterRange", AnnotationXmlConstants.Namespaces.BaseSchemaNamespace);

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Annotations/Anchoring/TextViewSelectionProcessor.cs

@@ -158,7 +158,7 @@ public override IList<ContentLocatorPart>
 
             ContentLocatorPart part = new ContentLocatorPart(TextSelectionProcessor.CharacterRangeElementName);// DocumentPageViewLocatorPart();
             part.NameValuePairs.Add(TextSelectionProcessor.CountAttribute, 1.ToString(NumberFormatInfo.InvariantInfo));
-            part.NameValuePairs.Add(TextSelectionProcessor.SegmentAttribute + 0.ToString(NumberFormatInfo.InvariantInfo), startOffset.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator[0] + endOffset.ToString(NumberFormatInfo.InvariantInfo));
+            part.NameValuePairs.Add(TextSelectionProcessor.SegmentAttribute + 0.ToString(NumberFormatInfo.InvariantInfo), startOffset.ToString(NumberFormatInfo.InvariantInfo) + TextSelectionProcessor.Separator + endOffset.ToString(NumberFormatInfo.InvariantInfo));
             part.NameValuePairs.Add(TextSelectionProcessor.IncludeOverlaps, Boolean.TrueString);
 
             res.Add(part);

src/Microsoft.DotNet.Wpf/src/PresentationFramework/Microsoft/Win32/FileDialog.cs

@@ -1612,7 +1612,7 @@ private string[] GetFilterExtensions()
             if (filter != null)
             {
                 // Filter strings are '|' delimited, so we split on them
-                string[] tokens = filter.Split(new char[] { '|' }, StringSplitOptions.RemoveEmptyEntries);
+                string[] tokens = filter.Split('|', StringSplitOptions.RemoveEmptyEntries);
 
                 // Calculate the index of the token containing extension(s) selected
                 // by the FilterIndex property.  Remember FilterIndex is one based.

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Annotations/Annotation.cs

@@ -966,7 +966,7 @@ private void Init()
         /// <summary>
         /// Colon used to split the parts of a qualified name attribute value
         /// </summary>
-        private static readonly char[] _Colon = new char[] { ':' };
+        private const char _Colon = ':';
 
         #endregion Private Fields
     }

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/ColorConvertedBitmapExtension.cs

@@ -47,7 +47,7 @@ public ColorConvertedBitmapExtension(
                 throw new ArgumentNullException("image");
             }
 
-            string[] tokens = ((string)image).Split(new char[] { ' ' });
+            string[] tokens = ((string)image).Split(' ');
 
             foreach (string str in tokens)
             {

src/Microsoft.DotNet.Wpf/src/PresentationFramework/System/Windows/Markup/BamlRecords.cs

@@ -2528,7 +2528,7 @@ internal override void WriteRecordData(BinaryWriter bamlBinaryWriter)
             if (ValueType != null && ValueType.IsEnum)
             {
                 uint uintValue = 0;
-                string [] enumValues = Value.Split(new Char[] { ',' });
+                string [] enumValues = Value.Split(',');
 
                 // if the Enum is a flag, then resolve each flag value in the enum value string.
                 foreach (string enumValue in enumValues)

src/Microsoft.DotNet.Wpf/src/WindowsBase/MS/Internal/IO/Packaging/Compoundfile/ContainerUtilities.cs

@@ -45,7 +45,6 @@ static internal class ContainerUtilities
         /// Used by ConvertBackSlashPathToStringArrayPath and 
         ///     ConvertStringArrayPathToBackSlashPath to separate path elements.
         static readonly internal char PathSeparator = Path.DirectorySeparatorChar;
-        static private readonly char[] _PathSeparatorArray = new char[] { PathSeparator };
         static readonly internal string PathSeparatorAsString = new string(ContainerUtilities.PathSeparator, 1);
 
         static private readonly CaseInsensitiveOrdinalStringComparer _stringCaseInsensitiveComparer = new CaseInsensitiveOrdinalStringComparer();
@@ -347,7 +346,7 @@ static internal string[] ConvertBackSlashPathToStringArrayPath(string backSlashP
 
             // Build the array
             string[] splitArray =
-                backSlashPath.Split(_PathSeparatorArray);
+                backSlashPath.Split(PathSeparator);
 
             // Look for empty strings in the array
             foreach (string arrayElement in splitArray)