Go back to the login page is nested within an iframe problem (MVC example)

Why 80% of the code can not do farming architect? >>>  

//首页
public ActionResult Index()
        {
            if (!Request.IsAuthenticated) //判断权限，没有登录就跳回登录页
            {string url =  Url.Action("Index", "Start", new {  area=""});
                Response.Write("parent.window.location.href('" + url + "');");
            }

            return View();
        }

 

Reproduced in: https: //my.oschina.net/garyun/blog/602748