private void odaDemirbasListesiToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (formDmrList == null)
     {
         formDmrList             = new FormOdaDemirbasListesi();
         formDmrList.FormClosed += new FormClosedEventHandler(FormDmrList_FormClosed);
         formDmrList.MdiParent   = this;
         formDmrList.Show();
     }
     else
     {
         formDmrList.Activate();
     }
 }
 private void FormDmrList_FormClosed(object sender, FormClosedEventArgs e)
 {
     formDmrList = null;
 }