private void buttonItem2_Click(object sender, EventArgs e)
{
if (PhongBanfrm == null || PhongBanfrm.IsDisposed)
{
PhongBanfrm = new frmPhongBan();
PhongBanfrm.MdiParent = this;
PhongBanfrm.Show();
}
else
{
PhongBanfrm.Activate();
}
}
private void btnPhong_Click(object sender, EventArgs e)
{
frmPhongBan PB = new frmPhongBan();
PB.ShowDialog();
}