title: Route table issue in MVC 3/4/5 application
body: <p>Lets say we have two controller HomeController and DocumentController and 
  there is a "Index" action method in HomeController and "Add" action method in DocumentController.</p>
  
  <p>In register route(global.asax) there is a entry of home/index. </p>
  
  <p>But when I try to access Document/Add It doesn't throw any page not found error.
  Ideally it should, as there is no entry for route "Document/Add" in register route in global asax.</p>
  
  <p>How come this happens ?</p>
  
  <p><strong>HomeController:</strong></p>
  
  <pre><code>public class HomeController : Controller
  {
      public ActionResult Index()
      {
          ViewBag.Message = "Modify this template to jump-start your ASP.NET MVC application.";
  
          return View();
      }
  }
  </code></pre>
  
  <p><strong>DocumentController :</strong></p>
  
  <pre><code>public class DocumentController : Controller
  {
  
      public ActionResult Add()
      {
          return View();
      }
  
  }
  </code></pre>
  
  <p><strong>RouteConfig:</strong></p>
  
  <pre><code>public class RouteConfig
  {
      public static void RegisterRoutes(RouteCollection routes)
      {
       routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
  
          routes.MapRoute(
              name: "Default",
              url: "{controller}/{action}/{id}",
              defaults: new { controller = "Home", action = "Index", id =        UrlParameter.Optional }
          );
      }
  }
  </code></pre>