Second MapRoute in asp.net MVC 4 doesn't work with parameters

Question

i want to add a second MapRoute to my first MVC 4 Project, well i added this code in Global.asax.vb

    routes.IgnoreRoute("{resource}.axd/{*pathInfo}")
    routes.MapRoute( _
        "Math", _
        "Calculator/{action}/{foo}/{intBar}", _
        New With {.controller = "Calculator", .action = "Add", .foo = ""} _
    )
    routes.MapRoute( _
        "Default", _
        "{controller}/{action}/{id}", _
        New With {.controller = "Default", .action = "Index", .id = ""} _
    )

and this is my controller /Controllers/CalculatorController.vb

   Function Add(         ByVal foo     As String, 
                Optional ByVal intBar? As Integer = 1) As ActionResult
        ViewData("Message") = foo & " Welt"
        Return View()

    End Function

Now my problem, what i am doing wrong?

localhost:18118/Calculator/Add/Hallo - Message is only " Welt" but where is "Hallo" ?

localhost:18118/Calculator/Add/Hallo/7 - Error 404 ? Why ?

I hope you can help/teach me. Thanks for your time!

Answer 1

The problem is caused by the fact, that your two routes "Math" and "Default" are defining different named parameters When you call:

localhost:18118/Calculator/Add/Hallo

Then the "Default" route is used and named parameters are:

• controller = calculator
• action = Add
• id = Hallo

But your Action Add requires parameter named foo. I would suggest, rename the foo parameter in the "Math" route mapping as id:

 routes.MapRoute( _
        "Math", _
        "Calculator/{action}/{id}/{intBar}", _ ' foo renamed to id
        New With {.controller = "Calculator", .action = "Add", .id = ""} _
    )

And rename the Action parameter as well: Function Add(ByVal id As String,... to make it working.

NOTE: renaming is suggestion to make it working, not saying that this is the best way how to do that...

Answer 2

I think it's because you're overriding the foo param from the URL with the .foo = "" statement in the defaults object. You map {foo} in your route, so it takes in your 'Hallo' string -- but then you replace it with the empty string.

Try taking out .foo = "" from your defaults object.