private void barButtonItem_DmTochuc_ItemClick(object sender, ItemClickEventArgs e)
{
if (formDMToChuc == null)
{
formDMToChuc = new F_Main_DMToChuc();
formDMToChuc.MdiParent = this;
formDMToChuc.FormClosed += new FormClosedEventHandler(formDMToChuc_FormClosed);
formDMToChuc.Show();
}
else
{
formDMToChuc.Activate();
}
}
void formDMToChuc_FormClosed(object sender, FormClosedEventArgs e)
{
formDMToChuc = null;
}