void danhsachintclick(object sender, RoutedEventArgs e)
 {
     frmdsinternet dsmy = new frmdsinternet();
     dsmy.Width = this.ActualWidth;
     dsmy.Height = this.ActualHeight;
     dsmy.Show();
 }
 private void ChildWindow_Closed(object sender, EventArgs e)
 {
     if (m_usr != "")
     {
         frmdsinternet frm = new frmdsinternet();
         frm.Width = this.ActualWidth;
         frm.Height = this.ActualHeight;
         frm.Show();
         frm.txttim.Text = m_usr;
     }
 }