Die Tcp-Socket-server in C#

Ich gefunden habe, dieses Stück code auf dem internet: es öffnet sich nicht einen server lauscht auf port 11000, wie ich erhofft hatte.

Was kann das problem sein? Ich normalerweise code in Delphi, deshalb bin ich etwas verloren. Ich habe einen entsprechenden client in Delphi, die funktioniert.

Ich bin mit demo-version von C# 2015.

    public static void StartListening()
    {
        //Data buffer for incoming data.
        byte[] bytes = new Byte[1024];

        //Establish the local endpoint for the socket.
        //Dns.GetHostName returns the name of the 
        //host running the application.
        IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());
        IPAddress ipAddress = ipHostInfo.AddressList[0];
        IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);

        //Create a TCP/IP socket.
        Socket listener = new Socket(AddressFamily.InterNetwork,
            SocketType.Stream, ProtocolType.Tcp);

        //Bind the socket to the local endpoint and 
        //listen for incoming connections.
        try
        {
            listener.Bind(localEndPoint);
            listener.Listen(10);

            //Start listening for connections.
            while (true)
            {
                //Console.WriteLine("Waiting for a connection...");
                //Program is suspended while waiting for an incoming connection.
                Socket handler = listener.Accept();
                data = null;

                //An incoming connection needs to be processed.
                while (true)
                {
                    bytes = new byte[1024];
                    int bytesRec = handler.Receive(bytes);
                    data += Encoding.ASCII.GetString(bytes, 0, bytesRec);
                    if (data.IndexOf("#") > -1)
                    {
                        break;
                    }
                }

                //Show the data on the console.
                //Console.WriteLine("Text received : {0}", data);

                //Echo the data back to the client.
                byte[] msg = Encoding.ASCII.GetBytes(data);

                handler.Send(msg);
                handler.Shutdown(SocketShutdown.Both);
                handler.Close();
            }

        }
        catch (Exception e)
        {
            Console.WriteLine(e.ToString());
        }

        //Console.WriteLine("\nPress ENTER to continue...");
        //Console.Read();

    }