我有一个 用 保存的 ActionResult

 try
            {
                //主键
                tEmployee.TemployeeId = Guid.NewGuid().ToString();
                tEmployee.Tcode = "wng";
                Db.TEmployee.InsertOnSubmit(tEmployee);
                Db.SubmitChanges();
                ViewData["msg"] = new Msg
                {
                    Title = "成功",
                    Content = "添加成功",
                    Type = 1,
                    Html = ""
                };
                UpdateModel(tEmployee);
                return View("Details", tEmployee);
            }

但为什么还回到 Details 中 ，表单的数据没有被更新呢？

             tEmployee.Tcode = "wng";