URL rewriting in Asp.net

public class Global : System.Web.HttpApplication    {        void Application_Start(object sender, EventArgs e)        {            // Code that runs on application startup            RegisterRoutes(RouteTable.Routes);        }        void RegisterRoutes(RouteCollection routes)        {            routes.MapPageRoute("", "home", "~/home.aspx");            routes.MapPageRoute("", "vetri/profile/{userid}", "~/vetri/profile.aspx");        } }