不解,,有关SOCKET问题

Question

服务器端
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Threading;
namespace TimeServer
{
    public class TimeServer
    {
        static void Main(string[] args)
        {
            try
            {
                TcpListener server = new TcpListener(5001);
                server.Start();
                Console.WriteLine("Waiting for connection...");
                while (true)
                {
                    Socket client = server.AcceptSocket();
                    Console.WriteLine("已连接DTU");
                                  ClinetHandler ch = new ClinetHandler(client);
              
                    while (true)
                    {
                        NetworkStream netStream = new NetworkStream(client);
                        string send = Console.ReadLine();
                        byte[] buffer = Encoding.ASCII.GetBytes(send);
                        netStream.Write(buffer, 0, buffer.Length);
                    }
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }
        class ClinetHandler
        {
            private Socket client;
            public ClinetHandler(Socket client)
            {
                this.client = client;
                Thread ClientThread = new Thread(new ThreadStart(ClientSession));
                ClientThread.Start();
            }
            public void ClientSession()
            {
                try
                {
                      NetworkStream netStream = new NetworkStream(client);
                    while (true)
                    {
                        byte[] rcd = new byte[128];
                        int i = netStream.Read(rcd, 0, rcd.Length);
                        if (rcd[0] == 0x68 && rcd[5] == 0x68 && rcd[i-1] == 0x16)
                        {
                            Console.WriteLine("I See");
                        }
                        string ree = Encoding.ASCII .GetString(rcd);
                        Console.WriteLine(ree);                    }                }
                catch (Exception e)
                {
                    Console.WriteLine(e.ToString());                }
                finally
                {
                    client.Close();
                }            }
           
             
        }
    }
}客户端
using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Net;
using System.Net.Sockets;
namespace IOClient
{
    public class TimeClient
    {
        TcpClient client;
        public TimeClient()
        {
            client = new TcpClient("localhost", 5001);  //localhost  127.0.0.1
        }
    
        static void Main(string[] args)
        {
            TimeClient tc = new TimeClient();
            Console.WriteLine("I connected!");
            Console.WriteLine("The Data is: ");
            
            String time = tc.Retrieve();
            Console.WriteLine(time);
            tc.SendData();  
        }
         public String Retrieve()
         {
            NetworkStream netStream = client.GetStream();
       
            while (true)
            {
                byte[] rcd = new byte[128];
                int i = netStream.Read(rcd, 0, rcd.Length);
                
                string ree = Encoding.ASCII.GetString(rcd);
                return ree;
            }            
        }
   
        public void SendData()
        {
            NetworkStream netStream = client.GetStream();
        
            byte[] buff = {0x68,0x12,0x34,0x56,0x78,0x68,0xA1,0x00,0x03,0xAB,0xCD,0xEF,0xEF,0x16};
            netStream.Write(buff, 0, buff.Length);
            while (true)
            {
                string send = Console.ReadLine();
                byte [] buffer = Encoding.ASCII.GetBytes(send);
                netStream.Write(buffer, 0, buffer.Length);
            }
        }
    }
}请问如何修改才可以在命令行,,服务器端和客户端两者都可以输入数据发送给对方,,现在只可以从客户端发送给服务器.         请各位指教下TKS