private void barButtonItem_DiaDiem_ItemClick(object sender, ItemClickEventArgs e)
{
if (formDSachDiaDiem == null)
{
formDSachDiaDiem = new F_Main_DSachDiaDiem();
formDSachDiaDiem.MdiParent = this;
formDSachDiaDiem.FormClosed += new FormClosedEventHandler(formDSachDiaDiem_FormClosed);
formDSachDiaDiem.Show();
}
else
{
formDSachDiaDiem.Activate();
}
}
void formDSachDiaDiem_FormClosed(object sender, FormClosedEventArgs e)
{
formDSachDiaDiem = null;
}