MVC, Dynamic routing, Unity, Determine if current controller exists in global.asax

Question

What I'm trying to do is dynamic routing for my application.

For instance, in Application_BeginRequest() I want to get the current controller and determine if it exists. If not, I want to add a set of routes that override the default routing so that my url looks like this

mysite.com/term from database

But, if the "term from database" is a valid controller, I want it to use the default routing

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

I already have my routes the way I want. Now I just need to get the current controller and determine if it exists. If I do not add my custom routes, I recieve this error:

The IControllerFactory 'MySite.Web.UnityControllerFactory' did not return a controller for a controller named 'term from database'.

Is there a way to use unity from the global to determine if the controller exists?

Thanks!

Answer 1

Why don't you create a utility helper class that registers routes from your database and then apply your controller routes in your global.asax?

As your DB routes are registered first, if it finds a valid route then it would use that one first. Or you could set it vice versa. As an extra note I would make sure your routes from your DB have an associated RouteName to avoid conflicts.

public class Global : HttpApplication
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        //call utility to register routes from db
        RouteHelper.RegisterRoutesFromDB(routes);

        //now define my standard routes
        routes.MapRoute(
            "Default",
            "{controller}/{action}/{id}",
            new { controller = "Home", action = "Index", id = "" }
        );

        ...