11asp.net===========cookis之记住用户名

 if (IsPostBack)
            {
                string userName = Request.Form["txtName"];
                Response.Cookies["userName"].Value = userName;
                Response.Cookies["userName"].Expires = DateTime.Now.AddDays(3);
            }
            else
            {
                if (Request.Cookies["userName"] != null)
                {
                    string userName = Request.Cookies["userName"].Value;
                    LoginUserName = userName;
                    //第二次登录时，再次往后延迟3天。
                    Response.Cookies["userName"].Value = userName;
                    Response.Cookies["userName"].Expires = DateTime.Now.AddDays(3);
                }
            }