RegEx timeout warning (#17716)

* RegEx timeout warning

* RegEx timeout warning

* Update aspnetcore/mvc/controllers/routing.md

Co-Authored-By: Kirk Larkin <6025110+serpent5@users.noreply.github.com>

Co-authored-by: Kirk Larkin <6025110+serpent5@users.noreply.github.com>

Author: Rick-Anderson

aspnetcore/fundamentals/routing.md

@@ -449,6 +449,8 @@ Using a template is generally the simplest approach to routing. Constraints and
 Complex segments are processed by matching up literal delimiters from right to left in a [non-greedy](#greedy) way. For example, `[Route("/a{b}c{d}")]` is a complex segment.
 Complex segments work in a particular way that must be understood to use them successfully. The example in this section demonstrates why complex segments only really work well when the delimiter text doesn't appear inside the parameter values. Using a [regex](/dotnet/standard/base-types/regular-expressions) and then manually extracting the values is needed for more complex cases.
 
+[!INCLUDE[](~/includes/regex.md)]
+
 This is a summary of the steps that routing performs with the template `/a{b}c{d}` and the URL path `/abcd`. The `|` is used to help visualize how the algorithm works:
 
 * The first literal, right to left, is `c`. So `/abcd` is searched from right and finds `/ab|c|d`.

aspnetcore/mvc/controllers/routing.md

@@ -524,6 +524,7 @@ The `RouteTokenTransformerConvention` is registered as an option in `ConfigureSe
 
 See [MDN web docs on Slug](https://developer.mozilla.org/docs/Glossary/Slug) for the definition of Slug.
 
+[!INCLUDE[](~/includes/regex.md)]
 <a name="routing-multiple-routes-ref-label"></a>
 
 ### Multiple attribute routes

aspnetcore/mvc/controllers/routing/samples/3.x/main/StartupSlugifyParamTransformer.cs

@@ -5,6 +5,7 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
+using System;
 using System.Text.RegularExpressions;
 
 namespace WebMvcRouting
@@ -63,9 +64,11 @@ public string TransformOutbound(object value)
         {
             if (value == null) { return null; }
 
-            // Slugify value
             return Regex.Replace(value.ToString(),
-                                 "([a-z])([A-Z])", "$1-$2").ToLowerInvariant();
+                                 "([a-z])([A-Z])",
+                                 "$1-$2",
+                                 RegexOptions.CultureInvariant,
+                                 TimeSpan.FromMilliseconds(100)).ToLowerInvariant();
         }
     }
     #endregion

aspnetcore/razor-pages/razor-pages-conventions.md

@@ -186,18 +186,11 @@ public void ConfigureServices(IServiceCollection services)
                     new SlugifyParameterTransformer()));
         });
 }
+```
 
-public class SlugifyParameterTransformer : IOutboundParameterTransformer
-{
-    public string TransformOutbound(object value)
-    {
-        if (value == null) { return null; }
+[!code-csharp[](~/mvc/controllers/routing/samples/3.x/main/StartupSlugifyParamTransformer.cs?name=snippet2)]
 
-        // Slugify value
-        return Regex.Replace(value.ToString(), "([a-z])([A-Z])", "$1-$2").ToLower();
-    }
-}
-```
+[!INCLUDE[](~/includes/regex.md)]
 
 ## Configure a page route