public ActionResult Create(HangSanXuat hangsanxuat)
        {
            if (ModelState.IsValid)
            {
                db.HangSanXuats.Add(hangsanxuat);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            ViewBag.MaQG = new SelectList(db.QuocGias, "MaQG", "TenQG", hangsanxuat.MaQG);
            return View(hangsanxuat);
        }
 public ActionResult Edit(HangSanXuat hangsanxuat)
 {
     if (ModelState.IsValid)
     {
         db.Entry(hangsanxuat).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     ViewBag.MaQG = new SelectList(db.QuocGias, "MaQG", "TenQG", hangsanxuat.MaQG);
     return View(hangsanxuat);
 }