void dadi_FormClosed(object sender, FormClosedEventArgs e)
{
dadi = null;
}
private void deleteADepartmentToolStripMenuItem_Click(object sender, EventArgs e)
{
if (dadi == null)
{
dadi = new DeleteAnDepartmentInfo();
dadi.MdiParent = this;
dadi.FormClosed += dadi_FormClosed;
dadi.Show();
}
else
{
dadi.Activate();
}
}