Example of WebAPI 2 Exception Filter

ExceptionFilterRegistration

public static class WebApiConfig{
    public static void Register(HttpConfiguration config)
    {
   
#if DEBUG
      config.Filters.Add(new DebugGeneralExceptionAttribute());
#endif

      webApiConfig . Filters. Add( new DbEntityValidationExceptionAttribute ());
      // Other configuration code...
     }
}

WebApi2ExceptionFilter

 public class DebugGeneralExceptionAttribute : ExceptionFilterAttribute
 {
    public override void OnException( HttpActionExecutedContext context)
    {
      var messageParsedOfNewLineEtc = Regex .Replace(context . Exception. Message, @"\t|\n|\r" , "" );
      var response = new HttpResponseMessage ( HttpStatusCode. InternalServerError)
      {
        Content = new StringContent(context . Exception. Message),
        ReasonPhrase = "Something has gone terribly wrong :(   " + messageParsedOfNewLineEtc
      };
      context . Response = response;
    }
  }