public BEL_SANPHAM(BEL_SANPHAM sp)
{
this._IDSP = sp.IDSP;
this._TenSP = sp.TenSP;
this._DonGia = sp.DonGia;
this._TrangThai = sp.TrangThai;
}
public BEL_CHITIETHOADON(BEL_SANPHAM sp)
{
this._IDSP = sp.IDSP;
this._Soluong = sp.SoLuong;
this._ThanhTien = (sp.SoLuong * sp.DonGia);
}