RSystem-MVC-Fork/RSystem/App_Start/RouteConfig.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Routing;

namespace RSystem
{
    public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
            routes.MapMvcAttributeRoutes();


            routes.MapRoute(
                name: "WithLanguage",
                url: "{lang}/{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
                constraints: new { lang = "pl|en" },
                namespaces: new[] { "RSystem.Controllers" }
            );

            routes.MapRoute(
                name: "Defaut",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },                
                namespaces: new[] { "RSystem.Controllers" }
            );            
        }
    }
}