# System.ComponentModel.DataAnnotations

``` diff
 namespace System.ComponentModel.DataAnnotations {
     [AttributeUsageAttribute(AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property, AllowMultiple=false)]
     public class RegularExpressionAttribute : ValidationAttribute {
-        public RegularExpressionAttribute(string pattern);
+        public RegularExpressionAttribute([StringSyntaxAttribute("Regex")] string pattern);
+        public TimeSpan MatchTimeout { get; }
     }
 }
```

