C#清除所有Cookes值

     protected void loginout_Click(object sender, EventArgs e)
        {
            string sCookieName;
            HttpCookie sCookie;
            int limit = Request.Cookies.Count;
            for (int i = 0; i < limit; i++)
            {
                sCookieName = Request.Cookies[i].Name;
                sCookie = new HttpCookie(sCookieName);
                sCookie.Expires = DateTime.Now.AddDays(-1);
                Response.Cookies.Add(sCookie);
            }
        }