Refactor : Enable CA2249

.editorconfig

@@ -214,6 +214,9 @@ dotnet_diagnostic.CA2245.severity = warning
 # CA2246: Assigning symbol and its member in the same statement
 dotnet_diagnostic.CA2246.severity = warning
 
+# CA2249: Use string.Contains instead of string.IndexOf to improve readability.
+dotnet_diagnostic.CA2249.severity = warning
+
 # IDE0005: Remove unnecessary usings
 dotnet_diagnostic.IDE0005.severity = warning
 
@@ -297,6 +300,8 @@ dotnet_diagnostic.CA1847.severity = suggestion
 dotnet_diagnostic.CA2008.severity = suggestion
 # CA2012: Use ValueTask correctly
 dotnet_diagnostic.CA2012.severity = suggestion
+# CA2249: Use string.Contains instead of string.IndexOf to improve readability.
+dotnet_diagnostic.CA2249.severity = suggestion
 # IDE0005: Remove unnecessary usings
 dotnet_diagnostic.IDE0005.severity = suggestion
 # IDE0044: Make field readonly

src/Http/Http.Abstractions/src/HostString.cs

@@ -43,7 +43,7 @@ public HostString(string host, int port)
         }
 
         int index;
-        if (host.IndexOf('[') == -1
+        if (!host.Contains('[')
             && (index = host.IndexOf(':')) >= 0
             && index < host.Length - 1
             && host.IndexOf(':', index + 1) >= 0)
@@ -162,7 +162,7 @@ public static HostString FromUriComponent(string uriComponent)
         if (!string.IsNullOrEmpty(uriComponent))
         {
             int index;
-            if (uriComponent.IndexOf('[') >= 0)
+            if (uriComponent.Contains('['))
             {
                 // IPv6 in brackets [::1], maybe with port
             }
@@ -172,7 +172,7 @@ public static HostString FromUriComponent(string uriComponent)
             {
                 // IPv6 without brackets ::1 is the only type of host with 2 or more colons
             }
-            else if (uriComponent.IndexOf("xn--", StringComparison.Ordinal) >= 0)
+            else if (uriComponent.Contains("xn--", StringComparison.Ordinal))
             {
                 // Contains punycode
                 if (index >= 0)

src/Http/Routing/src/Patterns/RoutePatternFactory.cs

@@ -571,7 +571,7 @@ public static RoutePatternLiteralPart LiteralPart(string content)
             throw new ArgumentException(Resources.Argument_NullOrEmpty, nameof(content));
         }
 
-        if (content.IndexOf('?') >= 0)
+        if (content.Contains('?'))
         {
             throw new ArgumentException(Resources.FormatTemplateRoute_InvalidLiteral(content));
         }

src/Middleware/Rewrite/src/RewriteRule.cs

@@ -59,7 +59,7 @@ public virtual void ApplyRule(RewriteContext context)
                 result = "/";
             }
 
-            if (result.IndexOf(Uri.SchemeDelimiter, StringComparison.Ordinal) >= 0)
+            if (result.Contains(Uri.SchemeDelimiter, StringComparison.Ordinal))
             {
                 string scheme;
                 HostString host;

src/Middleware/Rewrite/src/UrlActions/RedirectAction.cs

@@ -43,7 +43,7 @@ public override void ApplyAction(RewriteContext context, BackReferenceCollection
             return;
         }
 
-        if (pattern.IndexOf(Uri.SchemeDelimiter, StringComparison.Ordinal) == -1 && pattern[0] != '/')
+        if (!pattern.Contains(Uri.SchemeDelimiter, StringComparison.Ordinal) && pattern[0] != '/')
         {
             pattern = '/' + pattern;
         }
@@ -52,6 +52,7 @@ public override void ApplyAction(RewriteContext context, BackReferenceCollection
         // url can either contain the full url or the path and query
         // always add to location header.
         // TODO check for false positives
+
         var split = pattern.IndexOf('?');
         if (split >= 0 && QueryStringAppend)
         {

src/Middleware/Rewrite/src/UrlActions/RewriteAction.cs

@@ -59,7 +59,7 @@ public override void ApplyAction(RewriteContext context, BackReferenceCollection
         }
 
         // TODO PERF, substrings, object creation, etc.
-        if (pattern.IndexOf(Uri.SchemeDelimiter, StringComparison.Ordinal) >= 0)
+        if (pattern.Contains(Uri.SchemeDelimiter, StringComparison.Ordinal))
         {
             string scheme;
             HostString host;

src/Mvc/Mvc.TagHelpers/src/TagHelperOutputExtensions.cs

@@ -176,7 +176,7 @@ public static void AddClass(
 
         var encodedSpaceChars = SpaceChars.Where(x => !x.Equals('\u0020')).Select(x => htmlEncoder.Encode(x.ToString())).ToArray();
 
-        if (SpaceChars.Any(classValue.Contains) || encodedSpaceChars.Any(value => classValue.IndexOf(value, StringComparison.Ordinal) >= 0))
+        if (SpaceChars.Any(classValue.Contains) || encodedSpaceChars.Any(value => classValue.Contains(value, StringComparison.Ordinal)))
         {
             throw new ArgumentException(Resources.ArgumentCannotContainHtmlSpace, nameof(classValue));
         }
@@ -233,7 +233,7 @@ public static void RemoveClass(
 
         var encodedSpaceChars = SpaceChars.Where(x => !x.Equals('\u0020')).Select(x => htmlEncoder.Encode(x.ToString())).ToArray();
 
-        if (SpaceChars.Any(classValue.Contains) || encodedSpaceChars.Any(value => classValue.IndexOf(value, StringComparison.Ordinal) >= 0))
+        if (SpaceChars.Any(classValue.Contains) || encodedSpaceChars.Any(value => classValue.Contains(value, StringComparison.Ordinal)))
         {
             throw new ArgumentException(Resources.ArgumentCannotContainHtmlSpace, nameof(classValue));
         }

src/Shared/RangeHelper/RangeHelper.cs

@@ -45,7 +45,7 @@ public static (bool isRangeRequest, RangeItemHeaderValue? range) ParseRange(
         }
 
         // Perf: Check for a single entry before parsing it
-        if (rawRangeHeader.Count > 1 || (rawRangeHeader[0] ?? string.Empty).IndexOf(',') >= 0)
+        if (rawRangeHeader.Count > 1 || (rawRangeHeader[0] ?? string.Empty).Contains(','))
         {
             logger.LogDebug("Multiple ranges are not supported.");