private void LoadDonHang()
{
DataTable dt = DonHang.LayDSDHChuaCoPhieuNhap();
if (dt != null)
{
cmbDonDDH.ValueMember = "MasoDDH";
cmbDonDDH.DisplayMember = "MasoDDH";
cmbDonDDH.DataSource = dt;
}
}