Why does this route not work correctly?

Question

I'm seriously going crazy with this.

Here is what is in my Global.asax

routes.MapRoute("BlogDetails", "Blogs/{id}/{title}", new { controller = "Blogs", action = "Details", id = "" });
routes.MapRoute(
"Default",                                              // Route name
"{controller}/{action}/{id}",                           // URL with parameters
new { controller = "Home", action = "Index", id = "" }  // Parameter defaults
);

Those are the only two routes I have.

When I try to access

http://mysite/Blogs/Edit/1 it doesn't work I get this error

The parameters dictionary contains a null entry for parameter 'id' of non-nullable type 'System.Int32' for method 'System.Web.Mvc.ActionResult Details(Int32)' in 'mysite.Controllers.BlogsController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter.

Why does this keep happening?

Thanks

I should also add my controller code looks like this

//
// GET: /Blogs/Edit/5

[Authorize]
public ActionResult Edit(int id)
{
  // do a bunch of stuff and return something
}

Answer 1

Try the following

routes.MapRoute("BlogDetails", "Blogs/{id}/{title}",
 new { controller = "Blogs", action = "Details"},
 new { id = @"\d+" });

As far as MVC routes are concerned, {id} could be anything (even strings), so it matches Edit as a string, which can't go into the int id of your action.

Adding new { id= @"\\d+" } as an extra parameter tells the routing system to only match numbers.

http://www.asp.net/(S(pdfrohu0ajmwt445fanvj2r3))/learn/mvc/tutorial-24-cs.aspx

Answer 2

The 2 routes you are having are actually " confilicting " and in your case the first route gets picked instead of 2nd as you expect.

Maybe you need to modify your routes to remove the ambiguity:

routes.MapRoute("BlogDetails", "Blogs/{id}-{title}", new { controller = "Blogs", action = "Details", id = "" });
routes.MapRoute(
  "Default",                                              // Route name
  "{controller}/{action}/{id}",                           // URL with parameters
  new { controller = "Home", action = "Index", id = "" }  // Parameter defaults
);

This definition will clearly distinguish between: http://mysite/Blogs/Edit/1 and http://mysite/Blogs/1-first

or as Baddie mentioned try to add constraint to the route.