ActionLink/RouteLink not using specified actionName - asp.net-mvc

Question

On the Index.cshtml view of EuroController i have an ActionLink that i want to use the "IndexByYear" action of Euro controller:
#Html.ActionLink("Year 2006", "IndexByYear","Euro", new { id = "", year = 2006 }, null)
But the problem is that it goes to the Index() method, even though it's everything set on RouteConfig:
routes.MapRoute(
name: "Default",
url: "{controller}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
routes.MapRoute(
name: "Euro",
url: "{controller}/{year}/{id}",
defaults: new { controller = "Euro", action = "IndexByYear", year = DateTime.Now.Year, id = UrlParameter.Optional }
);
Here's the EuroController:
public ActionResult Index(int? id)
{
...
}
public ActionResult IndexByYear(int? id, int year)
{
...
}
Also this don't work, as it also goes to Index() method:
#Html.RouteLink("Ano 2006","Euro",new { id = "", year = 2006 },null)
If i manually navigate to domain/Euro/2016/1, then it uses the correct route. Seems like with no parameters it goes through the Default route.
My question is, why does the ActionLink don't use the IndexByYear as specified, or the RouteLink use the specified default (Euro) route?

Answer 1

If you want just the EuroController to have a "special" routing, you would want to do something like:
routes.MapRoute(
name: "Euro",
url: "euro/{year}/{id}",
defaults: new { controller = "Euro", action = "IndexByYear", year = DateTime.Now.Year, id = UrlParameter.Optional }
);
routes.MapRoute(
name: "DefaultNoController",
url: "{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
constraints: new { isMethodInHomeController = new RootRouteConstraint<Controllers.HomeController>() }
);
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
Where the constraint is defined like so:
public class RootRouteConstraint<T> : IRouteConstraint
{
public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
{
var rootMethodNames = typeof(T).GetMethods().Select(x => x.Name.ToLower());
return rootMethodNames.Contains(values["action"].ToString().ToLower());
}
}
This will match
domain/euro/1 to the Index action on EuroController
domain/euro/2008/1 to the IndexByYear action on EuroController
domain/ to the Index action on HomeController
domain/about to the About action on HomeController
domain/someothercontroller to the Index action on whatever other controllers you define
You may want to read https://msdn.microsoft.com/en-us/library/cc668201.aspx and https://www.asp.net/mvc/overview/older-versions-1/controllers-and-routing/creating-a-custom-route-constraint-cs