public ItemGioHang(int masp) { using (QuanLyBanHangContext db = new QuanLyBanHangContext()) { MaSP = masp; SanPham sp = db.SanPham.SingleOrDefault(s => s.MaSp == masp); TenSP = sp.TenSp; DonGia = sp.DonGia.Value; HinhAnh = sp.HinhAnh; SoLuong = 1; ThanhTien = SoLuong * DonGia; } }