C#的Socket简单实现消息发送

Socket一般用于网络之间的通信，在这里，实现的是服务端与客户端的简单消息通信。
首先是客户端的搭建，一般步骤是先建立Socket绑定本地的IP和端口，并对远端连接进行连接进行监听，这里的监听一般开启后台线程进行循环处理；如果远端有连接到本机的Socket的端口，则获取一个新的Socket对象并重新添加一个线程用于对远端地址进行消息通信（消息的收发），这样，服务端的Socket就简单实现，下面是winForm的具体实现。

一、先建立Socket的服务类SocketServerManager，用于对Socket各种操作的统一管理：

    public class SocketManager
    {
        Socket _socket = null;
        EndPoint _endPoint = null;
        bool _isListening = false;
        int BACKLOG = 10;

        public SocketManager(string ip, int port)
        {
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress _ip = IPAddress.Parse(ip);
            _endPoint = new IPEndPoint(_ip, port);
        }

        public void Start()
        {
            _socket.Bind(_endPoint); //绑定端口
            _socket.Listen(BACKLOG); //开启监听
            Thread acceptServer = new Thread(AcceptWork); //开启新线程处理监听
            acceptServer.IsBackground = true;
            _isListening = true;
            acceptServer.Start();
        }

        public void AcceptWork()
        {
            while (_isListening)
            {
                Socket acceptSocket = _socket.Accept();
                if (acceptSocket != null)
                {
                    Thread socketConnectedThread = new Thread(newSocketReceive);
                    socketConnectedThread.IsBackground = true;
                    socketConnectedThread.Start(acceptSocket);
                }
                Thread.Sleep(200);
            }
        }

        public void newSocketReceive(object obj)
        {
            Socket socket = obj as Socket;
            while (true)
            {
                try
                {
                    if (socket == null) return;
                    //这里向系统投递一个接收信息的请求，并为其指定ReceiveCallBack做为回调函数 
                    socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, ReceiveCallBack, buffer);
                }
                catch (Exception ex)
                {
                    return;
                }
                Thread.Sleep(100);
            }
        }

        private void ReceiveCallBack(IAsyncResult ar)
        {
        }
    }

上面是Socket管理类的模型，具体的方法是初始化和开启监听，接下来就是在Form的界面调用建立类和Start方法。

客户端同样是初始化socket，然后就不是监听socket，而是调用Connect连接指定的Socket地址，最后是开启新的线程接收和发送消息。

    public class SocketClientManager
    {
        public Socket _socket = null;
        public EndPoint endPoint = null;
        public bool _isConnected = false;

        public SocketClientManager(string ip, int port)
        {
            IPAddress _ip = IPAddress.Parse(ip);
            endPoint = new IPEndPoint(_ip, port);
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        }

        public void Start()
        {
            _socket.BeginConnect(endPoint, ConnectedCallback, _socket);
            _isConnected = true;
            Thread socketClient = new Thread(SocketClientReceive);
            socketClient.IsBackground = true;
            socketClient.Start();
        }

        public void SocketClientReceive()
        {
            while (_isConnected)
            {
                try {
                    _socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, ReceiveCallback, buffer);
                }
                catch (SocketException ex)
                {
                    _isConnected = false;
                }
                
                Thread.Sleep(100);
            }
        }

        public void ReceiveCallback(IAsyncResult ar)
        {
        }
    }

主要记住的是，客户端是监听Socket是固定的，是监听绑定地址的，每当有新的连接访问，则开启新的线程与之进行交互，而客户端只简单实现与服务端交互，服务端则只有一个。
Socket的进行发送与接收，一般是通过异步方法BeginReceive和BeginSend进行处理，方法一般带有回调函数，用于执行操作之后的处理。
还有就是连接的关闭，每关闭一个连接，先要结束在Socket所在的线程方法，我这里的处理是停止掉死循环的函数调用，每当线程所在函数执行完毕，则线程自动销毁。之后就是关闭所连接的socket。

下面是我程序的完整实现，为了方便socket的管理，我把服务器的所有与客户端对话的Socket统一用字典管理，并封装在SocketInfo的内部类中，消息的发送与接收必须先找到该连接socket。
最后就是界面的调用，完成Socket的网络消息交互。

下面是具体的实现及源码：

    public class SocketManager
    {
        public Dictionary<string,SocketInfo> _listSocketInfo = null;
        Socket _socket = null;
        public SocketInfo socketInfo = null;
        EndPoint _endPoint = null;
        bool _isListening = false;
        int BACKLOG = 10;

        public delegate void OnConnectedHandler(string clientIP);
        public event OnConnectedHandler OnConnected;
        public delegate void OnReceiveMsgHandler(string ip);
        public event OnReceiveMsgHandler OnReceiveMsg;
        public event OnReceiveMsgHandler OnDisConnected;

        public SocketManager(string ip, int port)
        {
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPAddress _ip = IPAddress.Parse(ip);
            _endPoint = new IPEndPoint(_ip, port);
            _listSocketInfo = new Dictionary<string, SocketInfo>();
        }

        public void Start()
        {
            _socket.Bind(_endPoint); //绑定端口
            _socket.Listen(BACKLOG); //开启监听
            Thread acceptServer = new Thread(AcceptWork); //开启新线程处理监听
            acceptServer.IsBackground = true;
            _isListening = true;
            acceptServer.Start();
        }

        public void AcceptWork()
        {
            while (_isListening)
            {
                Socket acceptSocket = _socket.Accept();
                if (acceptSocket != null && this.OnConnected != null)
                {
                    SocketInfo sInfo = new SocketInfo();
                    sInfo.socket = acceptSocket;
                    _listSocketInfo.Add(acceptSocket.RemoteEndPoint.ToString(), sInfo);
                    OnConnected(acceptSocket.RemoteEndPoint.ToString());
                    Thread socketConnectedThread = new Thread(newSocketReceive);
                    socketConnectedThread.IsBackground = true;
                    socketConnectedThread.Start(acceptSocket);
                }
                Thread.Sleep(200);
            }
        }

        public void newSocketReceive(object obj)
        {
            Socket socket = obj as Socket;
            SocketInfo sInfo = _listSocketInfo[socket.RemoteEndPoint.ToString()];
            sInfo.isConnected = true;
            while (sInfo.isConnected)
            {
                try
                {
                    if (sInfo.socket == null) return;
                    //这里向系统投递一个接收信息的请求，并为其指定ReceiveCallBack做为回调函数 
                    sInfo.socket.BeginReceive(sInfo.buffer, 0, sInfo.buffer.Length, SocketFlags.None, ReceiveCallBack, sInfo.socket.RemoteEndPoint);
                }
                catch (Exception ex)
                {
                    return;
                }
                Thread.Sleep(100);
            }
        }

        private void ReceiveCallBack(IAsyncResult ar)
        {
            EndPoint ep = ar.AsyncState as IPEndPoint;
            SocketInfo info = _listSocketInfo[ep.ToString()];
            int readCount = 0;
            try
            {
                if (info.socket == null) return;
                readCount = info.socket.EndReceive(ar);
            }catch(Exception ex){
                return;
            }
            if (readCount > 0)
            {
                //byte[] buffer = new byte[readCount];
                //Buffer.BlockCopy(info.buffer, 0, buffer, 0, readCount);
                if (readCount < info.buffer.Length)
                {
                    byte[] newBuffer = new byte[readCount];
                    Buffer.BlockCopy(info.buffer, 0, newBuffer, 0, readCount);
                    info.msgBuffer = newBuffer;
                }
                else
                {
                    info.msgBuffer = info.buffer;
                }
                string msgTip = Encoding.ASCII.GetString(info.msgBuffer);
                if (msgTip == "faild")
                {
                    info.isConnected = false;
                    if (this.OnDisConnected != null) OnDisConnected(info.socket.RemoteEndPoint.ToString());
                    _listSocketInfo.Remove(info.socket.RemoteEndPoint.ToString());
                    info.socket.Close();
                    return;
                }
                if (OnReceiveMsg != null) OnReceiveMsg(info.socket.RemoteEndPoint.ToString());
            }
        }

        public void SendMsg(string text, string endPoint)
        {
            if (_listSocketInfo.Keys.Contains(endPoint) && _listSocketInfo[endPoint] != null)
            {
                _listSocketInfo[endPoint].socket.Send(Encoding.ASCII.GetBytes(text));
            }
        }

        public void Stop()
        {
            _isListening = false;
            foreach (SocketInfo s in _listSocketInfo.Values)
            {
                s.socket.Close();
            }
        }

        public class SocketInfo
        {
            public Socket socket = null;
            public byte[] buffer = null;
            public byte[] msgBuffer = null;
            public bool isConnected = false;

            public SocketInfo()
            {
                buffer = new byte[1024 * 4];
            }
        }
    }

    public class SocketClientManager
    {
        public Socket _socket = null;
        public EndPoint endPoint = null;
        public SocketInfo socketInfo = null;
        public bool _isConnected = false;

        public delegate void OnConnectedHandler();
        public event OnConnectedHandler OnConnected;
        public event OnConnectedHandler OnFaildConnect;
        public delegate void OnReceiveMsgHandler();
        public event OnReceiveMsgHandler OnReceiveMsg;

        public SocketClientManager(string ip, int port)
        {
            IPAddress _ip = IPAddress.Parse(ip);
            endPoint = new IPEndPoint(_ip, port);
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        }

        public void Start()
        {
            _socket.BeginConnect(endPoint, ConnectedCallback, _socket);
            _isConnected = true;
            Thread socketClient = new Thread(SocketClientReceive);
            socketClient.IsBackground = true;
            socketClient.Start();
        }

        public void SocketClientReceive()
        {
            while (_isConnected)
            {
                SocketInfo info = new SocketInfo();
                try {
                    _socket.BeginReceive(info.buffer, 0, info.buffer.Length, SocketFlags.None, ReceiveCallback, info);
                }
                catch (SocketException ex)
                {
                    _isConnected = false;
                }
                
                Thread.Sleep(100);
            }
        }

        public void ReceiveCallback(IAsyncResult ar)
        {
            socketInfo = ar.AsyncState as SocketInfo;
            if (this.OnReceiveMsg != null) OnReceiveMsg();
        }

        public void ConnectedCallback(IAsyncResult ar)
        {
            Socket socket = ar.AsyncState as Socket;
            if (socket.Connected)
            {
                if (this.OnConnected != null) OnConnected();
            }
            else
            {
                if (this.OnFaildConnect != null) OnFaildConnect();
            }
        }

        public void SendMsg(string msg)
        {
            byte[] buffer = Encoding.ASCII.GetBytes(msg);
            _socket.Send(buffer);
        }

        public class SocketInfo
        {
            public Socket socket = null;
            public byte[] buffer = null;

            public SocketInfo()
            {
                buffer = new byte[1024 * 4];
            }
        }
    }

 

具体源码（.net4.5，vs2013）：具体源码 https://files.cnblogs.com/files/supheart/ServerBySocket.zip