asp.net mvc Error Redirect 處理錯誤頁面轉址

public class ErrorsController : Controller
{
    public ActionResult General(Exception exception)
    {
        return Content("General failure", "text/plain");
    }

    public ActionResult Http404()
    {
        return Content("Not found", "text/plain");
    }

    public ActionResult Http403()
    {
        return Content("Forbidden", "text/plain");
    }
}

protected void Application_Error()
{
    var exception = Server.GetLastError();
    var httpException = exception as HttpException;
    Response.Clear();
    Server.ClearError();
    var routeData = new RouteData();
    routeData.Values["controller"] = "Errors";
    routeData.Values["action"] = "General";
    routeData.Values["exception"] = exception;
    Response.StatusCode = 500;
    if (httpException != null)
    {
        Response.StatusCode = httpException.GetHttpCode();
        switch (Response.StatusCode)
        {
            case 403:
                routeData.Values["action"] = "Http403";
                break;
            case 404:
                routeData.Values["action"] = "Http404";
                break;
        }
    }

    IController errorsController = new ErrorsController();
    var rc = new RequestContext(new HttpContextWrapper(Context), routeData);
    errorsController.Execute(rc);
}