public GioHang(int iMaSP, int sl) { using (QuanLiBanHangModel db = new QuanLiBanHangModel()) { this.MaSP = iMaSP; SanPham sp = db.SanPhams.Single(n => n.MaSP == iMaSP); this.TenSP = sp.TenSP; this.HinhAnh = sp.HinhAnh; this.DonGia = sp.DonGia.Value; this.ThanhTien = DonGia * SoLuong; } }