public ActionResult Details(string id)
        {
            var model = AdminDemo.GetById(id);

            if (model == null)
            {
                return(View("Error"));
            }
            return(View(model));
        }
        public ActionResult Edit(string id)
        {
            var model = AdminDemo.GetById(id);

            if (model == null)
            {
                return(View("Error"));
            }
            ViewData.Model = model;
            return(View(model));
        }
 // GET: Admin
 public ActionResult AdminIndex() //管理员页
 {
     return(View(AdminDemo.GetAll()));
 }