Server accepting more clients TCP C#

Question

I'm trying to get a TCP server to connect with "multiple" TCP clients.

My project is basically 2 applications, which is designed like a 3 tier model. In the data tier for each applications i want a socket connection, so i can send data(string values) from one application to the other. As i have multiple methods in my logic tier that i want to send with my socket connection (same client basically), i have a problem with my TCP server - that it only accepts one TCP client (for some reason i don't know).

Do I need some kind of loop, so my server does'nt close the connection?

I'm pretty new to TCP programming, so I will be very happy to get some help to get going with my project.

This is my code for my TCP client:

public class Tx_Data
{
    const int PORT = 9000;

    private TcpClient clientSocket;

    public Tx_Data()
    {
        Console.WriteLine("Client startet");
        clientSocket = new TcpClient();
        clientSocket.Connect("192.168.122.169", 9000);
        Console.WriteLine("Forbindelse oprettet");
    }

    public void sendDataTCP(string puls, string QT, string QTc)
    {
        NetworkStream outToServer = clientSocket.GetStream();
        string line = "Puls: " + puls + ", QT: " + QT + ", QTc: "+ QTc;
        LIB.writeTextTCP(outToServer, line);
        outToServer.Flush();
    }

}

When i call the sendDataTCP method in one of my Logic Tier methods it looks like this:

  public void sendData()
    {
        Tx_Data tD = new Tx_Data();
        string puls = beregnPuls().ToString();
        string QT = beregn_QT().ToString();
        string QTc = beregn_QTC().ToString();
        tD.sendDataTCP(puls,QT,QTc);
    }

My TCP server that recieve the data looks like this atm:

  public class Rx_Alarm
{

    const int PORT = 9000;

    public Rx_Alarm()
    {
        TcpListener serverSocket = new TcpListener(IPAddress.Any, 9000);
        TcpClient clientSocket = default(TcpClient);
        serverSocket.Start();
        clientSocket = serverSocket.AcceptTcpClient();
        Console.WriteLine(">> Accept connection from client");


        NetworkStream io = clientSocket.GetStream();
        Console.WriteLine(LIB.readTextTCP(io));
    }
}

Answer 1

I don't know about TCPListeners, but in good old fashion socket programming. You can create server code and tell it how many clients to listen to

enter code here

var socListener = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
    var ipLocal = new IPEndPoint ( IPAddress.Any ,##Port Number##);
    //bind to local IP Address...
    socListener.Bind( ipLocal );
    //start listening...
    socListener.Listen (4); // where 4 is the number of clients to listen simultaneously
    // create the call back for any client connections...
    socListener.BeginAccept(new AsyncCallback ( OnClientConnect ),null);