public FSanPham()
{
InitializeComponent();
bus_SP = new BUSSanPham();
}
public FDatHang()
{
InitializeComponent();
busSP = new BUSSanPham();
busDH = new BUSDonHang();
}
public FCTDH()
{
InitializeComponent();
bus = new BUSDonHang();
busSP = new BUSSanPham();
}