Routing to the actions with same names but different parameters

Question

I have this set of routes:

        routes.MapRoute(             "IssueType",             "issue/{type}",             new { controller = "Issue", action = "Index" }         );          routes.MapRoute(             "Default", // Route name             "{controller}/{action}/{id}", // URL with parameters             new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults         ); 

Here is the controller class:

public class IssueController : Controller {     public ActionResult Index()     {         // todo: redirect to concrete type         return View();     }      public ActionResult Index(string type)     {         return View();     } } 

why, when i request http://host/issue i get The current request for action 'Index' on controller type 'IssueController' is ambiguous between the following action methods:
I expect that first one method should act when there is no parameters, and second one when some parameter specified.

where did i made mistake?

UPD: possible duplicate: Can you overload controller methods in ASP.NET MVC?

UPD 2: due to the link above - there is no any legal way to make action overloading, is it?

UPD 3: Action methods cannot be overloaded based on parameters (c) http://msdn.microsoft.com/en-us/library/system.web.mvc.controller%28VS.100%29.aspx

Answer 1

I would have one Index method that looks for a valid type variable

    public class IssueController : Controller   {       public ActionResult Index(string type)       {           if(string.isNullOrEmpty(type)){             return View("viewWithOutType");}         else{             return View("viewWithType");}      } } 

EDIT:

How about creating a custom attribute that looks for a specific request value as in this post StackOverflow

[RequireRequestValue("someInt")]  public ActionResult MyMethod(int someInt) { /* ... */ }   [RequireRequestValue("someString")]  public ActionResult MyMethod(string someString) { /* ... */ }   public class RequireRequestValueAttribute : ActionMethodSelectorAttribute {      public RequireRequestValueAttribute(string valueName) {          ValueName = valueName;      }      public override bool IsValidForRequest(ControllerContext controllerContext, MethodInfo methodInfo) {          return (controllerContext.HttpContext.Request[ValueName] != null);      }      public string ValueName { get; private set; }  }