C# ASP.NET MVC Controller with subfolders

In asp.net MVC Controllers, folders are ignored, as long as the cs files are set to compile they will be compiled into the DLL file and referenced by taking the class name (i.e ProductController) and dropping the word Controller from the end.

So the folder structure is largely up to yourself for whatever makes sense for your own project management.

If you are trying to get certain URLs to direct to certain controllers have a look at Routing instead.

Use routes.MapRoute for routing see below example:

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
    routes.MapRoute(
        "Blog",                                           // Route name
        "Archive/{entryDate}",                            // URL with parameters
        new { controller = "Archive", action = "Entry" }  // Parameter defaults
    );
    routes.MapRoute(
        "Default",                                              // Route name
        "{controller}/{action}/{id}",                           // URL with parameters
        new { controller = "Home", action = "Index", id = "" }  // Parameter defaults
    );
}