Why is this MVC route not working?

Question

here are two routes from my global.asax file. I'm trying to go to the second route and I'm getting a default 404 resource not found error.

When i remove the first route (listed in this example), it works.

How can i fix this, please?

Snippet of global.asax code

// GET: /user/PureKrome/Alert/69
routes.MapRoute(
    "User-Alert-Details",
    "user/{displayName}/alert/{alertId}",
    new { controller = "Account", action = "AlertDetails", alertId = 0 });

// GET: /user/PureKrome/Alert/create
routes.MapRoute(
    "User-Alert-Create",
    "user/{displayName}/alert/create",
    new { controller = "Account", action = "AlertCreate" });

Answer 1

Your first route is a "greedy" route and will happily accept "create" as the alertId in the last parameter. It appears that you intend the alertId parameter to be numeric only, so you should add a constraint to tell the route system that that last parameter must be numeric.

See this tutorial.

For example:

// GET: /user/PureKrome/Alert/69
routes.MapRoute(
    "User-Alert-Details",
    "user/{displayName}/alert/{alertId}",
    new { controller = "Account", action = "AlertDetails", alertId = 0 },
    new { alertId = @"\d+" });

// GET: /user/PureKrome/Alert/create
routes.MapRoute(
    "User-Alert-Create",
    "user/{displayName}/alert/create",
    new { controller = "Account", action = "AlertCreate" });

Note, you can also reverse the order of the routes, but even if you do, you should still include a constraint for correctness if you want alertId to always be a number.