void form_FormClosed(object sender, FormClosedEventArgs e)
 {
     form = null;
 }
 private void showForm(string status)
 {
     if (form == null)
     {
         form = new StatusForm();
         form.FormClosed += form_FormClosed;
         form.SizeChanged += form_SizeChanged;
         form.Status = status;
         form.Show();
     }
     else
     {
         form.Status = status;
         form.Activate();
     }
 }