public static string RemSku(string id)
        {
            try
            {
                DAO dao = new DAO();

                int rtn = dao.RemSku(Convert.ToInt32(id));

                if (rtn > 0)
                    return "True";
                else if (rtn == -1)
                    return "False1";
                else
                    return "False2";
            }
            catch (Exception ex)
            {
                return ex.Message;
            }
        }