private void listBoxForwardingPort_SelectedIndexChanged(object sender, EventArgs e)
{
this.listBoxForwardingInterface.SelectedIndex = this.listBoxForwardingPort.SelectedIndex;
this.listBoxForwardingMulticast.SelectedIndex = this.listBoxForwardingPort.SelectedIndex;
if (this.listBoxForwardingPort.SelectedIndex != -1)
this.numericUpDown1.Value = this.listBoxForwardingPort.SelectedIndex + 1;
}