Asp.net mvc 验证cookie不是持久的

我有下面的代码，根据其他stackoverflow的答案，它应该可以工作，但不能。我还缺什么吗

DateTime expiration = DateTime.Now.AddMinutes(30);
if (rememberMe)
{
    expiration = DateTime.Now.AddMonths(1);
}
HttpContext.Current.Response.Cookies.Clear();

var ticket = new FormsAuthenticationTicket(1, email, DateTime.Now, expiration, rememberMe,
guid.ToString(), FormsAuthentication.FormsCookiePath);

string encryptedTicket = FormsAuthentication.Encrypt(ticket);

var cookie = new HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket);
cookie.Expires = ticket.Expiration;
HttpContext.Current.Response.Cookies.Add(cookie);

并在

Application\u AuthenticateRequest

var authCookie = Request.Cookies.Get(FormsAuthentication.FormsCookieName);
if (authCookie == null) return;

var ticket = FormsAuthentication.Decrypt(authCookie.Value);
if (ticket == null) return;
...

和我的web.config条目：

<authentication mode="Forms">
     <forms loginUrl="~/Home/Index" timeout="30" /> <!--  30minutes
</authentication>

1-在asp.net项目的root web.config中，在system.web部分，将身份验证模式设置为“Forms”：

3-对于读取当前身份验证密钥使用：

using System.Web.Security;

FormsAuthentication.SetAuthCookie(userName,false);

var userName=controller.User.Identity.Name;

var userName=controller.User.Identity.Name;