C# Code Client Server

See more:

C#

Here is my code for asynchronous communication of client & server i.e multiple clients & single Server but my problem as soon as new client joins the server then server only send & recieve request from that recently connected pc not the pc that are already connected.The Connected Pc's are listed in combobox from the message is send to selected pc but it is not working...

This is use to send data to selected pc in combo box

private void sendData(String data)
{
    IPAddress ipep =IPAddress.Parse(comboBox1.SelectedItem.ToString());
    Socket server = new Socket(AddressFamily.InterNetwork , SocketType.Stream, ProtocolType.Tcp);
    IPEndPoint ipept = new IPEndPoint( ipep, hostPort);
    //TcpClient cl = new TcpClient(ipept.Address.ToString(), hostPort);
    NetworkStream nStream = tcpClient.GetStream();
    ASCIIEncoding asciidata = new ASCIIEncoding();
    byte[] buffer = asciidata.GetBytes(data);
    if (nStream.CanWrite)
    {
        nStream.Write(buffer, 0, buffer.Length);
        nStream.Flush();
    }
}

Thanx