public override RouteData GetRouteData(HttpContextBase httpContext)
{
var routeData = base.GetRouteData(httpContext);
if (routeData == null) return null; // Only look at the subdomain if this route matches in the first place.
string subdomain = httpContext.Request.Params["tenant"]; // A subdomain specified as a query parameter takes precedence over the hostname.
if (subdomain == null)
{
string host = httpContext.Request.Headers["Host"];
int index = host.IndexOf('.');
if (index >= 0)
subdomain = host.Substring(0, index);
}
if (subdomain != null)
{
routeData.Values["tenant"] = subdomain;
}
return routeData;
}