mvc routing

Routing is actually not part of the asp.net mvc component. But mvc depends on this asp.net components. To add a route to the route table, you can use the following code.

Route r = new Route("url", new SomeRouteHandler()); r.Constraints.Add("key", "value"); r.Defaults.Add("key", "value"); r.DataTokens.Add("key", "value"); RouteTable.Routes.Add("route_name", r); // or you can write the code in .net 3.0 syntax, they do the same job //but it looks cleaner. RouteTable.Routes.Add(new Route("url", new SomeRouteHandler()) { Constraints = new RouteValueDictionary(new { key = value }), Defaults = new RouteValueDictionary(new { key = value }), DataTokens = new RouteValueDictionary(new { key = value }), });

asp.net mvc, add some extension method to the RouteCollection like the following.

public static Route MapRoute(this RouteCollection routes, string name, string url, object defaults, object constraints, string[] namespaces) { if (routes == null) { throw new ArgumentNullException("routes"); } if (url == null) { throw new ArgumentNullException("url"); } Route route = new Route(url, new MvcRouteHandler()) { Defaults = new RouteValueDictionary(defaults), Constraints = new RouteValueDictionary(constraints) }; if ((namespaces != null) && (namespaces.Length > 0)) { route.DataTokens = new RouteValueDictionary(); route.DataTokens["Namespaces"] = namespaces; } routes.Add(name, route); return route; }

This method create a route use MvcRouteHandler as IRouteHandler. So if use this method, the MVC component comes into play. So you can these extension method to simplify the mvc routing

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

The default values only work when every URL parameters after the one with default also has a default value assigned. So the following code doesn't work.

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

The following code demo a catch-all parameter

routes.MapRoute("r2", "catch/{*all}", new { controller = "test", action = "catch", all="empty" }); public string Catch(string all) { return string.Format("<h1>all:{0}</h1>", all); }