C# TCP 客户端代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Socket测试代码
{
    public partial class Form1 : Form
    {
        List<Socket> ClientProxSocketList = new List<Socket>();

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        /// <summary>
        /// 启动服务端
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            //1、创建Socket对象
            //                           地址族：IPV4                套接字类型：流式      协议：TCP
            Socket socket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);

            //2、绑定监听端口
            socket.Bind(new IPEndPoint(IPAddress.Parse(textBox1.Text),int.Parse(textBox2.Text)));

            //3、设置监听队列
            socket.Listen(10);

            //4、循环等待客户端连接，这是第一次使用线程池，线程池中无限循环等待连接
            ThreadPool.QueueUserWorkItem(new WaitCallback(AcceptClientConnect),socket);
            
        }

        //第四步线程池中的委托方法
        //传入服务器的socket对象
        public void AcceptClientConnect(object socket)
        {
            var serverSocket = socket as Socket;
            this.AppendTextToTextLog("服务器端开始接受客户端连接。");
            //Socket serverSocket = (Socket)socket;
            while(true)
            {
                //调用Accept方法等待客户端的连接
                //连接后返回一个socket对象表示该次连接
                Socket proxSocket = serverSocket.Accept();
                this.AppendTextToTextLog(string.Format("客户端：{0}链接上了",proxSocket.RemoteEndPoint.ToString()));
                //将连接放入数组，因为可能有多个客户端与服务器进行连接，需要对他们都进行保存，以后调用的时候更方便。
                ClientProxSocketList.Add(proxSocket);
                //对于刚刚建立起来的连接，不停地接收当前连接的客户端发来的消息，这是第二次使用线程池，线程池中无限循环接收信息
                ThreadPool.QueueUserWorkItem(new WaitCallback(ReceiveData), proxSocket);
            }
        }

        /// <summary>
        /// 还是那个面方法线程池中调用的委托方法
        /// 接收客户端的消息
        /// </summary>
        /// <param name="socket"></param>
        public void ReceiveData(object socket)
        {
            //转换类型
            var peoxSocket = socket as Socket;
            byte[] data = new byte[1024*1024];
            while(true)
            {
                int len = 0;
                try
                {
                    len = peoxSocket.Receive(data, 0, data.Length, SocketFlags.None);
                }
                catch(Exception ex)
                {
                    //异常退出
                    AppendTextToTextLog(string.Format("客户端：{0}非正常退出", peoxSocket.RemoteEndPoint.ToString()));
                    ClientProxSocketList.Remove(peoxSocket);
                    return;  //让方法结束，终结当前客户端数据的异步线程
                }
                
                //把接收到的数据放到界面上
                string str = Encoding.Default.GetString(data,0,len);

                //接收到结束信息
                if(len<=0)
                {
                    //客户端正常退出
                    AppendTextToTextLog(string.Format("客户端：{0}正常退出", peoxSocket.RemoteEndPoint.ToString()));
                    //移除列表中的客户端连接
                    ClientProxSocketList.Remove(peoxSocket);
                    return;  //让方法结束，终结当前客户端数据的异步线程
                }
                //接收到正常信息
                AppendTextToTextLog(string.Format("接收到客户端：{0}的消息是：{1}",peoxSocket.RemoteEndPoint.ToString(),str));

            }
        }

        public void AppendTextToTextLog(string text)
        {
            if (textLog.InvokeRequired)
            {
                textLog.Invoke(new Action<string>(s => {
                    this.textLog.Text = string.Format("{0}\r\n{1}", s, textLog.Text);
                }), text);
            } else
            {
                this.textLog.Text = string.Format("{0}\r\n{1}",text,textLog.Text);
            }
        }

        /// <summary>
        /// 发送消息
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button2_Click(object sender, EventArgs e)
        {
            foreach (var proxSocket in ClientProxSocketList)
            {
                //先判断是否处于连接状态
                if(proxSocket.Connected)
                {
                    byte[] data = Encoding.Default.GetBytes(textBox4.Text);
                    proxSocket.Send(data,0,data.Length,SocketFlags.None);
                }
            }
        }
    }
}