public ActionResult Creat(Document_Lang documentItem)
 {
     if (ModelState.IsValid)
     {
         dbContext.Documents_Lang.Add(documentItem);
         dbContext.SaveChanges();
         return null;
     }
     return new HttpStatusCodeResult(400, "lỗi tạo gallery ngôn ngữ");
 }
 public ActionResult Update(Document_Lang documentItem)
 {
     if (ModelState.IsValid)
     {
         dbContext.Entry(documentItem).State = EntityState.Modified;
         dbContext.SaveChanges();
         return null;
     }
     else
     {
         return new HttpStatusCodeResult(400, "lỗi update gallery ngôn ngữ");
     }
 }