How to use a SubDomain as Route Value in MVC2

first:

I did read and tried to implemented this and this and that, but I failed completely :(

my route is like:

routes.MapRoute开发者_如何学Go(
    "DefaultRoute",
    "{calurl}/{controller}/{action}/{id}",
    new { calurl = "none", controller = "Subscriber", action = "Index", id = UrlParameter.Optional }
);

and I'm trying to use as

"{calurl}.domain.com",
"{controller}/{action}/{id}"

so the routed value calurl would always come from the subdomain.

and I could have links like:

http://demo.domain.com/Subscriber/Register

as of today I have

http://domain.com/demo/Subscriber/Register

What I have tried

I tried to create my own CustomRoute using the example of the links above (all 3, one at a time), and I end up always screwing everything.

and I'm keep thinking that it's to much code just to change RouteValue["calurl"] to the subdomain.

What/How can I do this?

I am not sure if Routing extends to the actual domain name, as the domain or sub-domain should'nt have any effect on the working of a site/application.

I would suggest building your own sub-domain detection on each request. This keeps Routing and the Sub-domain detection separate and will help with testing etc..

This may help:

public static string GetSubDomain()
        {
            string subDomain = String.Empty;

            if (HttpContext.Current.Request.Url.HostNameType == UriHostNameType.Dns)
            {
                subDomain = Regex.Replace(HttpContext.Current.Request.Url.Host, "((.*)(\\..*){2})|(.*)", "$2").Trim().ToLower();
            }

            if (subDomain == String.Empty)
            {
                subDomain = HttpContext.Current.Request.Headers["Host"].Split('.')[0];
            }

            return subDomain.Trim().ToLower();
        }

If you have IIS7, why not use a URL Rewrite rule?

This would probably be better than doing a hack job with your routes, and IIS would do what it does best.

Probably something like this:

<rule name="rewriteSubdomains" stopProcessing="true">
  <match url="(.*).domain.com/(.*)" />
  <action type="Rewrite" url="domain.com/{R:1}/{R:2}" />
</rule>

This way, your route will handle the subdomain correctly, as it comes into the app differently.