private void StartUpSocket()
{
    try
        {
            string portStr = "1234";
            int port = System.Convert.ToInt32(portStr);
            IPAddress ipAdd = IPAddress.Parse("127.0.0.1");
            // Create the listening socket...
            m_mainSocket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
            IPEndPoint ipLocal = new IPEndPoint(ipAdd, port);
            // Bind to local IP Address...
            m_mainSocket.Bind(ipLocal);
            // Start listening...
            m_mainSocket.Listen(7);
        }
        catch (SocketException se)
        {
            MessageBox.Show(se.Message);
        }
}