public void CreateUpdateProduct_get(string id, string datajson, string type, string callback)
        {
            var dal      = new ProductDAL();
            var result   = dal.CreateUpdateData(id, datajson, type);
            var userdata = JsonConvert.SerializeObject(result);

            if (string.IsNullOrEmpty(callback))
            {
                Response.Write(userdata);
            }
            else
            {
                Response.Write(callback + "(" + userdata + ")");
            }
        }