private void ttmiDatHang_Click(object sender, EventArgs e)
{
FormDatHang frm = new FormDatHang();
frm.MdiParent = this;
frm.Show();
}
private void HienThiFormDatHang(string name)
{
if (!HienThiForm(name))
{
FormDatHang formDatHang = new FormDatHang();
formDatHang.MdiParent = this;
formDatHang.Show();
}
}