private void pnHopDong_Click(object sender, EventArgs e)
{
a.ColorClick(sender);
ucDSKhachHang khachhang = new ucDSKhachHang();
form.changeUC(khachhang, pnNhanVien);
}
// sự kiện click
private void label2_Click(object sender, EventArgs e)
{
a.LabelClick(sender);
ucDSKhachHang khachhang = new ucDSKhachHang();
form.changeUC(khachhang, pnNhanVien);
}