Example of how to use SubdomainRoute class

AdminAreaRegistration.cs

public class AdminAreaRegistration : AreaRegistration
{
    public override string AreaName
    {
        get { return "Admin"; }
    }

    public override void RegisterArea(AreaRegistrationContext context)
    {
        context.Routes.Add("Admin_Home", new SubdomainRoute(
            "admin",
            "",
            new { area = this.AreaName, controller = "Home", action = "Index" },
            new string[] { "SubdomainRouting.Areas.Admin.Controllers" }
        ));

        context.Routes.Add("Admin_Login", new SubdomainRoute(
            "admin",
            "login",
            new { area = this.AreaName, controller = "Login", action = "Index" },
            new string[] { "SubdomainRouting.Areas.Admin.Controllers" }
        ));
    }
}