// start up the WPF application
// set the handler for the Checked event
ToggleButton channelButton1 = new ToggleButton();
channelButton1.Checked += (s, e) =>
     ThreadPool.QueueUserWorkItem(SetTcpChannel, 1);

try
    {
        int channel = (int)state;
        EnsureTcpSocket();
        // more logic to do stuff with channel
        // that we don't care about for SO
        ...
    }
    catch (Exception e)
    {
        // just for illustration
        // this is where I expected the code to return
        ...
    }

if (_tcp == null)
    {
        // this is not a valid ip/port since the
        // target machine is not running (test condition)
        // but that's ok, I should get some exception
        // and continue debugging...right?
        _tcp = new TcpClient(ip, port);
    }