注销session

  //Session.RemoveAll();
            Session.Clear();
            Session.Abandon();
            Response.Clear();
            Response.Buffer = true;
            Response.Expires = 0;
            Response.ExpiresAbsolute = DateTime.Now.AddDays(-1);
            Response.AddHeader("pragma", "no-cache");
            Response.AddHeader("cache-control", "private");
            Response.CacheControl = "no-cache";
            Response.Write("<script   language=\"javascript\">   top.location.href=\"login.aspx\";</script>");