public ActionResult Create(AssessItem model)
 {
     if (ModelState.IsValid) {
         db.AssessItems.Add(model);
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     return View();
 }
 public ActionResult Edit(AssessItem model)
 {
     try
     {
         AssessItem item = db.AssessItems.Find(model.AssessItemID);
         UpdateModel(item);
         db.SaveChanges();
         return RedirectToAction("Details", new { id = model.AssessItemID });
     }
     catch
     {
         ModelState.AddModelError("", "修改错误!");
         return View();
     }
 }