实验代码如下：

string roles = "";
string[] rolesList = Roles.GetRolesForUser(username);
foreach (string item in rolesList) roles += item + ",";

FormsAuthentication.SetAuthCookie(username, IsPersistent);
HttpCookie cookie = FormsAuthentication.GetAuthCookie(username, IsPersistent);

FormsAuthenticationTicket oldTicket = FormsAuthentication.Decrypt(cookie.Value);
FormsAuthenticationTicket newTicket = new FormsAuthenticationTicket(1, oldTicket.Name, oldTicket.IssueDate, DateTime.Now.AddMinutes(60), oldTicket.IsPersistent, roles, FormsAuthentication.FormsCookiePath);

cookie.Value = FormsAuthentication.Encrypt(newTicket);
HttpContext.Current.Response.SetCookie(cookie);

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webconfig 中的timeout=10

结果发现cookie的过期时间是10分钟而不是60分钟，也就是说 SetCookie没起到作用，感觉很纳闷 :(


请高手支招，谢谢！
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