How to add or customize routing constraints to avoid multiple actions were found
===

When trying to find solution for this below question:

http://stackoverflow.com/questions/11724749/mvc-web-api-route-with-default-action-not-working/11725968#11725968

Mostly I run across the problems "multiple actions were found". If routing mechanism find out there are more than one actions matched with a route, it throws out the exception 500.

For example, there are two actions:

        public IEnumerable<String> Active()
        {
            var result = new List<string> { "active1", "active2" };
            return result;
        }

        public IEnumerable<string> Get()
        {
            return new[] { "value1", "value2" };
        }

which match with default route:

     routes.MapHttpRoute(
              name: "DefaultApi",
              routeTemplate: "api/{controller}/{id}",
              defaults: new { id = RouteParameter.Optional }
          );

My question: how I can add or customize routing constraints which allow me to avoid the error "multiple actions were found" by choosing specified action (choose the first matched action is also okay).

Thanks
