MVC Filter登录验证

        public ActionResult Index()
        {
            //return Content("hello index!");
            return View();
        
        }
        [HttpGet]
        public ActionResult Login()
        {
            return View();
        }

        [HttpPost]
        public ActionResult Login(string username, string password)
        { 
            if(username=="111"&&password=="111")
            {
                Session["UUU"] = "111";
                return RedirectToAction("Index");
            }
            else
            {
                return Content("登录失败！");
            }
        
        }

<h2>Index</h2>
<text>主页运行成功</text>

<form action="/Login/Login" method="post">
    用户名<input type="text" name="username" value="" />
    密码<input type="text" name="password" value="" />
    <input type="submit" name="name" value="提交" />

</form>

using System.Web.Mvc;//别引用错了


 public class CheckLoginFilter:IAuthorizationFilter  
    {


        public void OnAuthorization(AuthorizationContext filterContext)
        {
            string controllerName = filterContext.ActionDescriptor.ControllerDescriptor.ControllerName;
            string actionName = filterContext.ActionDescriptor.ActionName;
            if (controllerName == "Login" && actionName == "Login")
            {
                
            }
            else
            {
                if (filterContext.HttpContext.Session["UUU"] == null)
                {
                    //ContentResult contexts = new ContentResult();
                    //contexts.Content = ("没有登录");
                    //filterContext.Result=contexts;
                    filterContext.HttpContext.Response.Redirect("/Login/Login");
                     
                    
                }
            }
        }
    }