ASP.NET MVC routing with one mandatory parameter and one optional parameter?

Question

I've been working on a large MVC application over the past month or so, but this is the first time I've ever needed to define a custom route handler, and I'm running into some problems. Basically I have two parameters to pass. The first one is required and the second one is optional.

I'm following this answer here.

Here is my custom route:

routes.MapRoute(
    "MyRoute",
    "{controller}/{action}/{param1}/{param2}",
    new { 
        controller = "MyController", 
        action = "MyAction", 
        param1 = "", 
        param2 = "" // I have also tried "UrlParameter.Optional" here.
    }
);

And my action method signature:

public ActionResult MyAction(string param1, string param2)

If I try the URL http://[myserver]/MyController/MyAction/Test1/Test2 then it works like I expect it to, with param1 = "Test1" and param2 = "Test2"

If I try the URL http://[myserver]/MyController/MyAction/Test1 then both parameters are null.

Hopefully somebody can tell me what I'm doing wrong here, because I'm lost.

Answer 1

Try this

routes.MapRoute("MyRoute",
                 "myRoute/{param1 }/{param2 }",
                 new { controller = "MyController", action = "MyAction", param2 = UrlParameter.Optional },
                 new { param2 = @"\w+" });

you can specify one parameter as optional by using "UrlParameter.Optional" and specified second one with DataType means if you pass integer value then DataType (@"\d+") and for string i have mention above.

NOTE: Sequence of parameter is very important Optional parameter must pass at last and register your new route Before Default Route In Gloab.asax.

then you action link like

<a href="@Url.RouteUrl("MyRoute", new { param2 = "Test1",param1 = "Test2"})">Test</a>

OR with one parameter

  <a href="@Url.RouteUrl("MyRoute", new { param2 = "Test1"})">Test</a>

In you Controller

 public ActionResult MyAction(string param2,string param1)
 {
   return View()
 }