ASP .NET Routing with Web Forms

Question

Is it possible to add a general route for all pages, or do I have to register each route? I work on a .NET web forms project and I am using ASP .NET Routing.

Currently I am using this to register the routes:

protected void Application_Start(Object sender, EventArgs e) 
{ 
   RegisterRoutes(RouteTable.Routes); 
} 

void RegisterRoutes(RouteCollection routes) 
{ 
   routes.MapPageRoute("MainPage", "{param1}/{param2}/MainPage.aspx/{*pathInfo}", "~/MainPage.aspx"); 
}