public JsonResult GetDanhSachLichSuDuyet(int?DuBao)
        {
            var model = db.APAX_DANHSACHLICHSUDUYETTIEPNHANCHUYENLOP(DuBao).ToList();
            var json  = Json(model, JsonRequestBehavior.AllowGet);

            json.MaxJsonLength = int.MaxValue;
            return(json);
        }