ASP.NET MVC路径如何实现这样的参数传递www.example.com/abcdef

默认如果是www.example.com/会定位到Home/Index
如果想使用www.example.com/abcdef实现Home/Index/id
把abcdef作为传入Home/Index的id而不是认为是abcdef的controller
相关于www.example.com/?id=abcdef
应该如何实现？

        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
        );

routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optiona