public void Delete(HinhThucDang dm)
 {
     en.DeleteObject(dm);
 }
 public int InsertToHinhThucDang()
 {
     var sp = new HinhThucDang();
         sp.NgayDang = DateTime.Now;
         sp.ThanhToan = "Chưa Thanh Toán";
         sp.OID = 1;
         HTDSPRes.AddHinhThucDang(sp);
         HTDSPRes.Save();
         return sp.HinhThucDang_ID;
 }
 public void AddHinhThucDang(HinhThucDang dm)
 {
     var q = en.HinhThucDang.Max(i => (int?)i.HinhThucDang_ID) ?? 1;
     dm.HinhThucDang_ID = q + 1;
     en.AddObject("HinhThucDang", dm);
 }
 public int InsertToHinhThucDang(int idAccount)
 {
     var sp = new HinhThucDang();
         sp.NgayDang = DateTime.Now;
         sp.ThanhToan = "ChuaThanhToan";
         sp.OID = idAccount;
         HTDSPRes.AddHinhThucDang(sp);
         HTDSPRes.Save();
         return sp.HinhThucDang_ID;
 }