MapRouting default querystring values?

问题

I have this route map (notice that topicName is ignored):

routes.MapRoute(
                "Topics", // Route name
               "Topic/{topicName}/{action}",
                new { controller = "Topic", action = "AddQuestion" });  

And I want it to defaultly map to this Url: http://localhost:51421/Topic/SomeName/AddQuestion?topicId=1 (or if that's not possible,to this url: http://localhost:51421/Topic/SomeName/AddQuestion/topicId/1)
(which should invoke this action:

public ActionResult AddQuestion(int topicId)
        {
            return View();
        }  

)
But either way I need all this data in the url.
What's the correct way to do that?

回答1:

You could add a default route:

routes.MapRoute(
    "Topics",
    "Topic/{topicName}/{action}/{topicId}",
    new { controller = "Topic", action = "AddQuestion", topicId = "1" }
);

routes.MapRoute(
    "Default",
    "{controller}/{action}/{topicId}",
    new { controller = "Topic", action = "AddQuestion", topicId = "1" }
);

来源：https://stackoverflow.com/questions/6039886/maprouting-default-querystring-values