C#- Socket实现服务器与多个客户端通信

　　因为工作需要，做一个C#的小DEMO来调试程序，好久没有写过SOCKET在网上找到一篇，代码看起来比较清晰明了。于是转载记录在这里，原文网址是：https://blog.csdn.net/luming666/article/details/79125453

　　Server端代码：

class Program
{
    //创建一个和客户端通信的套接字
    static Socket SocketWatch = null;
    //定义一个集合，存储客户端信息
    static Dictionary<string, Socket> ClientConnectionItems = new Dictionary<string, Socket> { };
 
    static void Main(string[] args)
    {
        //端口号（用来监听的）
        int port = 6000;
 
        //string host = "127.0.0.1";
        //IPAddress ip = IPAddress.Parse(host);
        IPAddress ip = IPAddress.Any;
 
        //将IP地址和端口号绑定到网络节点point上  
        IPEndPoint ipe = new IPEndPoint(ip, port);
 
        //定义一个套接字用于监听客户端发来的消息，包含三个参数（IP4寻址协议，流式连接，Tcp协议）  
        SocketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        //监听绑定的网络节点  
        SocketWatch.Bind(ipe);
        //将套接字的监听队列长度限制为20  
        SocketWatch.Listen(20);
 
 
        //负责监听客户端的线程:创建一个监听线程  
        Thread threadwatch = new Thread(WatchConnecting);
        //将窗体线程设置为与后台同步，随着主线程结束而结束  
        threadwatch.IsBackground = true;
        //启动线程     
        threadwatch.Start();
 
        Console.WriteLine("开启监听......");
        Console.WriteLine("点击输入任意数据回车退出程序......");
        Console.ReadKey();
 
        SocketWatch.Close();
 
        //Socket serverSocket = null;
 
        //int i=1;
        //while (true)
        //{
        //    //receive message
        //    serverSocket = SocketWatch.Accept();
        //    Console.WriteLine("连接已经建立！");
        //    string recStr = "";
        //    byte[] recByte = new byte[4096];
        //    int bytes = serverSocket.Receive(recByte, recByte.Length, 0);
        //    //recStr += Encoding.ASCII.GetString(recByte, 0, bytes);
        //    recStr += Encoding.GetEncoding("utf-8").GetString(recByte, 0, bytes);
 
        //    //send message
        //    Console.WriteLine(recStr);
 
        //    Console.Write("请输入内容：");
        //    string sendStr = Console.ReadLine();
 
        //    //byte[] sendByte = Encoding.ASCII.GetBytes(sendStr);
        //    byte[] sendByte = Encoding.GetEncoding("utf-8").GetBytes(sendStr);
 
        //    //Thread.Sleep(4000);
 
        //    serverSocket.Send(sendByte, sendByte.Length, 0);
        //    serverSocket.Close();
        //    if (i >= 100)
        //    {
        //        break;
        //    }
        //    i++;
        //}
            
        //sSocket.Close();
        //Console.WriteLine("连接关闭！");
 
 
        //Console.ReadLine();
    }
 
    //监听客户端发来的请求  
    static void WatchConnecting()
    {
        Socket connection = null;
 
        //持续不断监听客户端发来的请求     
        while (true)
        {
            try
            {
                connection = SocketWatch.Accept();
            }
            catch (Exception ex)
            {
                //提示套接字监听异常     
                Console.WriteLine(ex.Message);
                break;
            }
 
            //客户端网络结点号  
            string remoteEndPoint = connection.RemoteEndPoint.ToString();
            //添加客户端信息  
            ClientConnectionItems.Add(remoteEndPoint, connection);
            //显示与客户端连接情况
            Console.WriteLine("
[客户端"" + remoteEndPoint + ""建立连接成功！ 客户端数量：" + ClientConnectionItems .Count+ "]");
 
            //获取客户端的IP和端口号  
            IPAddress clientIP = (connection.RemoteEndPoint as IPEndPoint).Address;
            int clientPort = (connection.RemoteEndPoint as IPEndPoint).Port;
 
            //让客户显示"连接成功的"的信息  
            string sendmsg = "[" + "本地IP：" + clientIP + " 本地端口：" + clientPort.ToString() + " 连接服务端成功！]";
            byte[] arrSendMsg = Encoding.UTF8.GetBytes(sendmsg);
            connection.Send(arrSendMsg);
 
            //创建一个通信线程      
            Thread thread = new Thread(recv);
            //设置为后台线程，随着主线程退出而退出 
            thread.IsBackground = true;
            //启动线程     
            thread.Start(connection);
        }
    }
 
    /// <summary>
    /// 接收客户端发来的信息，客户端套接字对象
    /// </summary>
    /// <param name="socketclientpara"></param>    
    static void recv(object socketclientpara)
    {
        Socket socketServer = socketclientpara as Socket;
 
        while (true)
        {
            //创建一个内存缓冲区，其大小为1024*1024字节  即1M     
            byte[] arrServerRecMsg = new byte[1024 * 1024];
            //将接收到的信息存入到内存缓冲区，并返回其字节数组的长度    
            try
            {
                int length = socketServer.Receive(arrServerRecMsg);
 
                //将机器接受到的字节数组转换为人可以读懂的字符串     
                string strSRecMsg = Encoding.UTF8.GetString(arrServerRecMsg, 0, length);
 
                //将发送的字符串信息附加到文本框txtMsg上     
                Console.WriteLine("
[客户端：" + socketServer.RemoteEndPoint + " 时间：" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff")+ "]
" + strSRecMsg);
 
                //Thread.Sleep(3000);
                //socketServer.Send(Encoding.UTF8.GetBytes("[" + socketServer.RemoteEndPoint + "]："+strSRecMsg));
                //发送客户端数据
                if (ClientConnectionItems.Count > 0)
                {
                    foreach (var socketTemp in ClientConnectionItems)
                    {
                        socketTemp.Value.Send(Encoding.UTF8.GetBytes("[" + socketServer.RemoteEndPoint + "]：" + strSRecMsg));
                    }
                }
            }
            catch (Exception)
            {
                ClientConnectionItems.Remove(socketServer.RemoteEndPoint.ToString());
                //提示套接字监听异常  
                Console.WriteLine("
[客户端"" + socketServer.RemoteEndPoint + ""已经中断连接！ 客户端数量：" + ClientConnectionItems.Count+"]");
                //关闭之前accept出来的和客户端进行通信的套接字 
                socketServer.Close();
                break;
            }
        }
    }
}

　　Client端代码：

class Program
{
    //创建1个客户端套接字和1个负责监听服务端请求的线程  
    static Thread ThreadClient = null;
    static Socket SocketClient = null;
 
    static void Main(string[] args)
    {
        try
        {
            int port = 6000;
            string host = "127.0.0.1";//服务器端ip地址
 
            IPAddress ip = IPAddress.Parse(host);
            IPEndPoint ipe = new IPEndPoint(ip, port);
 
            //定义一个套接字监听  
            SocketClient = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
 
            try
            {
                //客户端套接字连接到网络节点上，用的是Connect  
                SocketClient.Connect(ipe);
            }
            catch (Exception)
            {
                Console.WriteLine("连接失败！
");
                Console.ReadLine();
                return;
            }
 
            ThreadClient = new Thread(Recv);
            ThreadClient.IsBackground = true;
            ThreadClient.Start();
 
            Thread.Sleep(1000);
            Console.WriteLine("请输入内容<按Enter键发送>：
");
            while(true)
            {
                string sendStr = Console.ReadLine();
                ClientSendMsg(sendStr);
            }
 
            //int i = 1;
            //while (true)
            //{
            //    Console.Write("请输入内容：");
            //    string sendStr = Console.ReadLine();
 
            //    Socket clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            //    clientSocket.Connect(ipe);
            //    //send message
            //    //byte[] sendBytes = Encoding.ASCII.GetBytes(sendStr);
            //    byte[] sendBytes = Encoding.GetEncoding("utf-8").GetBytes(sendStr);
 
            //    //Thread.Sleep(4000);
 
            //    clientSocket.Send(sendBytes);
 
            //    //receive message
            //    string recStr = ""; 
            //    byte[] recBytes = new byte[4096];
            //    int bytes = clientSocket.Receive(recBytes, recBytes.Length, 0);
            //    //recStr += Encoding.ASCII.GetString(recBytes, 0, bytes);
            //    recStr += Encoding.GetEncoding("utf-8").GetString(recBytes, 0, bytes);
            //    Console.WriteLine(recStr);
 
            //    clientSocket.Close();
            //    if (i >= 100)
            //    {
            //        break;
            //    }
            //    i++;
            //}
                
            //Console.ReadLine();
            //return;
 
            //string result = String.Empty;
 
        }
        catch (Exception ex) 
        {
            Console.WriteLine(ex.Message);
            Console.ReadLine();
        }
    }
 
    //接收服务端发来信息的方法    
    public static void Recv()
    {
            int x = 0;
        //持续监听服务端发来的消息 
        while (true)
        {
            try
            {
                //定义一个1M的内存缓冲区，用于临时性存储接收到的消息  
                byte[] arrRecvmsg = new byte[1024 * 1024];
 
                //将客户端套接字接收到的数据存入内存缓冲区，并获取长度  
                int length = SocketClient.Receive(arrRecvmsg);
 
                //将套接字获取到的字符数组转换为人可以看懂的字符串  
                string strRevMsg = Encoding.UTF8.GetString(arrRecvmsg, 0, length);
                if (x == 1)
                {
                    Console.WriteLine("
服务器：" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff") + "
" + strRevMsg+"
");
                        
                }
                else
                {
                    Console.WriteLine(strRevMsg + "
");
                    x = 1;
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("远程服务器已经中断连接！" + ex.Message + "
");
                break;
            }
        }
    }
 
    //发送字符信息到服务端的方法  
    public static void ClientSendMsg(string sendMsg)
    {
        //将输入的内容字符串转换为机器可以识别的字节数组     
        byte[] arrClientSendMsg = Encoding.UTF8.GetBytes(sendMsg);
        //调用客户端套接字发送字节数组     
        SocketClient.Send(arrClientSendMsg);
    }    
}

测试结果：
server端：

client端：

代码下载地址：http://download.csdn.net/download/luming666/10217302