c#异步Socket Tcp服务器实现
程序员文章站
2022-04-21 11:34:38
...
使用的是TcpListener来实现的异步服务器
代码
服务器核心代码 AsyncServer.cs
////// 异步SOCKET 服务器 /// public class AsyncServer : IDisposable { #region Fields ////// 服务器程序允许的最大客户端连接数 /// private int _maxClient; ////// 当前的连接的客户端数 /// private int _clientCount; ////// 服务器使用的异步socket /// private Socket _serverSock; ////// 客户端会话列表 /// private List_clients; private bool disposed = false; #endregion #region Properties /// /// 服务器是否正在运行 /// public bool IsRunning { get; private set; } ////// 监听的IP地址 /// public IPAddress Address { get; private set; } ////// 监听的端口 /// public int Port { get; private set; } ////// 通信使用的编码 /// public Encoding Encoding { get; set; } #endregion #region Ctors ////// 异步Socket TCP服务器 /// /// 监听的端口 public AsyncServer(int listenPort) : this(IPAddress.Any, listenPort,1024) { } ////// 异步Socket TCP服务器 /// /// 监听的终结点 public AsyncServer(IPEndPoint localEP) : this(localEP.Address, localEP.Port,1024) { } ////// 异步Socket TCP服务器 /// /// 监听的IP地址 /// 监听的端口 /// 最大客户端数量 public AsyncServer(IPAddress localIPAddress, int listenPort,int maxClient) { this.Address = localIPAddress; this.Port = listenPort; this.Encoding = Encoding.Default; _maxClient = maxClient; _clients = new List(); _serverSock = new Socket(localIPAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp); } #endregion #region Server /// /// 启动服务器 /// ///异步TCP服务器 public AsyncServer Start() { if (!IsRunning) { IsRunning = true; _serverSock.Bind(new IPEndPoint(this.Address, this.Port)); _serverSock.Listen(1024); _serverSock.BeginAccept(new AsyncCallback(HandleAcceptConnected), _serverSock); } return this; } ////// 启动服务器 /// /// /// 服务器所允许的挂起连接序列的最大长度 /// ///异步TCP服务器 public AsyncServer Start(int backlog) { if (!IsRunning) { IsRunning = true; _serverSock.Bind(new IPEndPoint(this.Address, this.Port)); _serverSock.Listen(backlog); _serverSock.BeginAccept(new AsyncCallback(HandleAcceptConnected), _serverSock); } return this; } ////// 停止服务器 /// ///异步TCP服务器 public AsyncServer Stop() { if (IsRunning) { IsRunning = false; _serverSock.Close(); //TODO 关闭对所有客户端的连接 } return this; } #endregion #region Receive ////// 处理客户端连接 /// /// private void HandleAcceptConnected(IAsyncResult ar) { if (IsRunning) { Socket server = (Socket)ar.AsyncState; Socket client = server.EndAccept(ar); //检查是否达到最大的允许的客户端数目 if (_clientCount == _maxClient) { //TODO 触发事件 RaiseServerException(null); } else { Session session = new Session(client); lock (_clients) { _clients.Add(session); _clientCount++; RaiseClientConnected(session); //触发客户端连接事件 } session.RecvDataBuffer = new byte[client.ReceiveBufferSize]; //开始接受来自该客户端的数据 client.BeginReceive(session.RecvDataBuffer, 0, session.RecvDataBuffer.Length, SocketFlags.None, new AsyncCallback(HandleDataReceived), session); } //接受下一个请求 server.BeginAccept(new AsyncCallback(HandleAcceptConnected), ar.AsyncState); } } ////// 处理客户端数据 /// /// private void HandleDataReceived(IAsyncResult ar) { if (IsRunning) { Session session = (Session)ar.AsyncState; Socket client = session.ClientSocket; try { //如果两次开始了异步的接收,所以当客户端退出的时候 //会两次执行EndReceive int recv = client.EndReceive(ar); if (recv == 0) { //TODO 触发事件 (关闭客户端) CloseSession(session); RaiseNetError(session); return; } //TODO 处理已经读取的数据 ps:数据在session的RecvDataBuffer中 RaiseDataReceived(session); //TODO 触发数据接收事件 } catch (SocketException ex) { //TODO 异常处理 RaiseNetError(session); } finally { //继续接收来自来客户端的数据 client.BeginReceive(session.RecvDataBuffer, 0, session.RecvDataBuffer.Length, SocketFlags.None, new AsyncCallback(HandleDataReceived), session); } } } #endregion #region Send ////// 发送数据 /// /// 接收数据的客户端会话 /// 数据报文 public void Send(Session session, byte[] data) { Send(session.ClientSocket,data); } ////// 异步发送数据至指定的客户端 /// /// 客户端 /// 报文 public void Send(Socket client, byte[] data) { if (!IsRunning) throw new InvalidProgramException("This TCP Scoket server has not been started."); if (client == null) throw new ArgumentNullException("client"); if (data == null) throw new ArgumentNullException("data"); client.BeginSend(data, 0, data.Length, SocketFlags.None, new AsyncCallback(SendDataEnd), client); } ////// 发送数据完成处理函数 /// /// 目标客户端Socket private void SendDataEnd(IAsyncResult ar) { ((Socket)ar.AsyncState).EndSend(ar); } #endregion #region Events ////// 接收到数据事件 /// public event EventHandlerDataReceived; private void RaiseDataReceived(Session session) { if (DataReceived != null) { DataReceived(this, new AsyncEventArgs(session)); } } /// /// 与客户端的连接已建立事件 /// public event EventHandlerClientConnected; /// /// 与客户端的连接已断开事件 /// public event EventHandlerClientDisconnected; /// /// 触发客户端连接事件 /// /// private void RaiseClientConnected(Session session) { if (ClientConnected != null) { ClientConnected(this, new AsyncEventArgs(session)); } } ////// 触发客户端连接断开事件 /// /// private void RaiseClientDisconnected(Socket client) { if (ClientDisconnected != null) { ClientDisconnected(this, new AsyncEventArgs("连接断开")); } } ////// 网络错误事件 /// public event EventHandlerNetError; /// /// 触发网络错误事件 /// /// private void RaiseNetError(Session session) { if (NetError != null) { NetError(this, new AsyncEventArgs(session)); } } ////// 异常事件 /// public event EventHandlerServerException; /// /// 触发异常事件 /// /// private void RaiseServerException(Session session) { if (ServerException != null) { ServerException(this, new AsyncEventArgs(session)); } } #endregion #region Close ////// 关闭一个与客户端之间的会话 /// /// 需要关闭的客户端会话对象 public void CloseSession(Session session) { if (session != null) { session.Datagram = null; session.RecvDataBuffer = null; _clients.Remove(session); _clientCount--; //TODO 触发关闭事件 session.Close(); } } ////// 关闭所有的客户端会话,与所有的客户端连接会断开 /// public void CloseAllClient() { foreach (Session client in _clients) { CloseSession(client); } _clientCount = 0; _clients.Clear(); } ////// Performs application-defined tasks associated with freeing, /// releasing, or resetting unmanaged resources. /// public void Dispose() { Dispose(true); GC.SuppressFinalize(this); } ////// Releases unmanaged and - optionally - managed resources /// ///true to release /// both managed and unmanaged resources;false /// to release only unmanaged resources. protected virtual void Dispose(bool disposing) { if (!this.disposed) { if (disposing) { try { Stop(); if (_serverSock != null) { _serverSock = null; } } catch (SocketException ex) { //TODO RaiseServerException(null); } } disposed = true; } } #endregion }
其中使用了一个Session类，来封装对客户端的连接
Session,cs
////// 客户端与服务器之间的会话类 /// public class Session { #region 字段 ////// 接收数据缓冲区 /// private byte[] _recvBuffer; ////// 客户端发送到服务器的报文 /// 注意:在有些情况下报文可能只是报文的片断而不完整 /// private string _datagram; ////// 客户端的Socket /// private Socket _clientSock; #endregion #region 属性 ////// 接收数据缓冲区 /// public byte[] RecvDataBuffer { get { return _recvBuffer; } set { _recvBuffer = value; } } ////// 存取会话的报文 /// public string Datagram { get { return _datagram; } set { _datagram = value; } } ////// 获得与客户端会话关联的Socket对象 /// public Socket ClientSocket { get { return _clientSock; } } #endregion ////// 构造函数 /// /// 会话使用的Socket连接 public Session(Socket cliSock) { _clientSock = cliSock; } ////// 关闭会话 /// public void Close() { //关闭数据的接受和发送 _clientSock.Shutdown(SocketShutdown.Both); //清理资源 _clientSock.Close(); } }
事件类
class AsyncEventArgs : EventArgs
{
///
/// 提示信息
///
public string _msg;
public Session _sessions;
///
/// 是否已经处理过了
///
public bool IsHandled { get; set; }
public AsyncEventArgs(string msg)
{
this._msg = msg;
IsHandled = false;
}
public AsyncEventArgs(Session session)
{
this._sessions = session;
IsHandled = false;
}
public AsyncEventArgs(string msg, Session session)
{
this._msg = msg;
this._sessions = session;
IsHandled = false;
}
}