public ActionResult Delete(int id, FormCollection collection)
        {
            string msg = "删除失败";

            try
            {
                if (id != 0)
                {
                    var attachment = attachmentDAL.GetAttachment(id);
                    ////先删除子表,再删除主表
                    //foreach (var role in account.Role) {
                    //    var RoleModel = roleDAL.GetRoleByID(role.RoleID);
                    //    account.Role.Remove(RoleModel);
                    //}
                    int count = attachmentDAL.Delete(attachment);
                    if (count < 0)
                    {
                        return(Content(msg));
                    }
                }
                // TODO: Add delete logic here
                //return RedirectToAction("Index");
                msg = "删除成功";
                return(Content(msg));
            }
            catch
            {
                return(Content(msg));
                //return View();
            }
        }
 /// <summary>
 /// 删除一条数据
 /// </summary>
 public bool Delete(string ID)
 {
     return(dal.Delete(ID));
 }