TCP自動重連

網上模板：

public class Socket_wrapper { public static Socket theSocket = null; private static string remoteHost = "192.168.1.14"; private static int remotePort = 6666; private static String SockErrorStr = null; private static ManualResetEvent TimeoutObject = new ManualResetEvent(false); private static Boolean IsconnectSuccess = false; //異步鏈接狀況，由異步鏈接回調函數置位 
        private static object lockObj_IsConnectSuccess = new object(); /// 設置心跳 ///   
        private static void SetXinTiao() { //byte[] inValue = new byte[] { 1, 0, 0, 0, 0x20, 0x4e, 0, 0, 0xd0, 0x07, 0, 0 };// 首次探測時間20 秒, 間隔偵測時間2 秒 
            byte[] inValue = new byte[] { 1, 0, 0, 0, 0x88, 0x13, 0, 0, 0xd0, 0x07, 0, 0 };// 首次探測時間5 秒, 間隔偵測時間2 秒 
            theSocket.IOControl(IOControlCode.KeepAliveValues, inValue, null); } /// 建立套接字+異步鏈接函數 ///   
        ///   
        private static bool socket_create_connect() { IPAddress ipAddress = IPAddress.Parse(remoteHost); IPEndPoint remoteEP = new IPEndPoint(ipAddress, remotePort); theSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); theSocket.SendTimeout = 1000; SetXinTiao();//設置心跳參數 

            #region 異步鏈接代碼 TimeoutObject.Reset(); //復位timeout事件 
            try { theSocket.BeginConnect(remoteEP, connectedCallback, theSocket); } catch (Exception err) { SockErrorStr = err.ToString(); return false; } if (TimeoutObject.WaitOne(10000, false))//直到timeout，或者TimeoutObject.set() 
 { if (IsconnectSuccess) { return true; } else { return false; } } else { SockErrorStr = "Time Out"; return false; } #endregion } /// 異步鏈接回調函數 ///   
        ///   
        static void connectedCallback(IAsyncResult iar) { #region <remarks>
            /// 一、置位IsconnectSuccess 
            #endregion </remarks>

            lock (lockObj_IsConnectSuccess) { Socket client = (Socket)iar.AsyncState; try { client.EndConnect(iar); IsconnectSuccess = true; //StartKeepAlive(); //開始KeppAlive檢測 
 } catch (Exception e) { //Console.WriteLine(e.ToString()); 
                    SockErrorStr = e.ToString(); IsconnectSuccess = false; } finally { TimeoutObject.Set(); } } } /// 同步receive函數 ///   
        ///   
        ///   
        public string socket_receive(byte[] readBuffer) { while (true) { try { if (theSocket == null) { if (!socket_create_connect()) { Thread.Sleep(1000); continue; } } else if (!theSocket.Connected) { if (!IsSocketConnected()) if (!Reconnect()) { Thread.Sleep(1000); continue; } } int bytesRec = theSocket.Receive(readBuffer); if (bytesRec == 0) { //warning 0 bytes received
                        if (!Reconnect()) { Thread.Sleep(1000); continue; } } return Encoding.ASCII.GetString(readBuffer, 0, bytesRec); } catch (SocketException se) { //print se.ErrorCode 
                    throw; } } } /// 同步send函數 ///   
        ///   
        ///   
        public bool socket_send(string sendMessage) { if (checkSocketState()) { return SendData(sendMessage); } return false; } /// 同步發送 ///   
        ///   
        ///   
        public static bool SendData(string dataStr) { bool result = false; if (dataStr == null || dataStr.Length < 0) return result; try { byte[] cmd = Encoding.Default.GetBytes(dataStr); int n = theSocket.Send(cmd); if (n < 1) result = false; } catch (Exception ee) { SockErrorStr = ee.ToString(); result = false; } return result; } /// 當socket.connected爲false時，進一步肯定下當前鏈接狀態 ///   
        ///   
        private bool IsSocketConnected() { #region remarks
            /******************************************************************************************** * 當Socket.Conneted爲false時， 若是您須要肯定鏈接的當前狀態，請進行非阻塞、零字節的 Send 調用。 * 若是該調用成功返回或引起 WAEWOULDBLOCK 錯誤代碼 (10035)，則該套接字仍然處於鏈接狀態； * 不然，該套接字再也不處於鏈接狀態。 * Depending on http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.connected.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-2 ********************************************************************************************/
            #endregion

            #region 過程
            // This is how you can determine whether a socket is still connected. 
            bool connectState = true; bool blockingState = theSocket.Blocking; try { byte[] tmp = new byte[1]; theSocket.Blocking = false; theSocket.Send(tmp, 0, 0); //Console.WriteLine("Connected!"); 
                connectState = true; //若Send錯誤會跳去執行catch體，而不會執行其try體裏其以後的代碼 
 } catch (SocketException e) { // 10035 == WSAEWOULDBLOCK 
                if (e.NativeErrorCode.Equals(10035)) { //Console.WriteLine("Still Connected, but the Send would block"); 
                    connectState = true; } else { //Console.WriteLine("Disconnected: error code {0}!", e.NativeErrorCode); 
                    connectState = false; } } finally { theSocket.Blocking = blockingState; } //Console.WriteLine("Connected: {0}", client.Connected); 
            return connectState; #endregion } /// 斷線重連函數 ///   
        ///   
        private static bool Reconnect() { //關閉socket 
 theSocket.Shutdown(SocketShutdown.Both); theSocket.Disconnect(true); IsconnectSuccess = false; theSocket.Close(); //建立socket 
            return socket_create_connect(); } /// 檢測socket的狀態 ///   
        ///   
        public static bool checkSocketState() { try { if (theSocket == null) { return socket_create_connect(); } else if (IsconnectSuccess) { return true; } else//已建立套接字，但未connected 
 { #region 異步鏈接代碼 TimeoutObject.Reset(); //復位timeout事件 
                    try { IPAddress ipAddress = IPAddress.Parse(remoteHost); IPEndPoint remoteEP = new IPEndPoint(ipAddress, remotePort); theSocket.BeginConnect(remoteEP, connectedCallback, theSocket); SetXinTiao();//設置心跳參數 
 } catch (Exception err) { SockErrorStr = err.ToString(); return false; } if (TimeoutObject.WaitOne(2000, false))//直到timeout，或者TimeoutObject.set() 
 { if (IsconnectSuccess) { return true; } else { return false; } } else { SockErrorStr = "Time Out"; return false; } #endregion } } catch (SocketException se) { SockErrorStr = se.ToString(); return false; } } }

我的簡化改進：

public void SocketCreateConnect() { try { tcpClient = new TcpClient(localEP); tcpClient.BeginConnect(remoteEP.Address, remoteEP.Port, ConnectedCallback, tcpClient); } catch { } } /// 異步鏈接回調函數 ///   
        /// 
        private void ConnectedCallback(IAsyncResult iar) { #region <remarks>
            /// 一、置位IsconnectSuccess 
            #endregion </remarks>

            lock (lockObj_IsConnectSuccess) { TcpClient tcpClient = (TcpClient)iar.AsyncState; try { tcpClient.EndConnect(iar); //IsconnectSuccess = true;
 Receive_Radar29(); } catch (Exception e) { //IsconnectSuccess = false;
                    Thread.Sleep(10000); tcpClient.BeginConnect(remoteEP.Address, remoteEP.Port, ConnectedCallback, tcpClient); } } } /// 當socket.connected爲false時，進一步肯定下當前鏈接狀態 ///   
        ///   
        private bool IsSocketConnected() { #region remarks
            /******************************************************************************************** * 當Socket.Conneted爲false時， 若是您須要肯定鏈接的當前狀態，請進行非阻塞、零字節的 Send 調用。 * 若是該調用成功返回或引起 WAEWOULDBLOCK 錯誤代碼 (10035)，則該套接字仍然處於鏈接狀態； * 不然，該套接字再也不處於鏈接狀態。 * Depending on http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.connected.aspx?cs-save-lang=1&cs-lang=csharp#code-snippet-2 ********************************************************************************************/
            #endregion

            #region 過程
            // This is how you can determine whether a socket is still connected. 
            bool connectState = true; bool blockingState = tcpClient.Client.Blocking; try { byte[] tmp = new byte[1]; tcpClient.Client.Blocking = false; tcpClient.Client.Send(tmp, 0, 0); //Console.WriteLine("Connected!"); 
                connectState = true; //若Send錯誤會跳去執行catch體，而不會執行其try體裏其以後的代碼 
 } catch (SocketException e) { // 10035 == WSAEWOULDBLOCK 
                if (e.NativeErrorCode.Equals(10035)) { //Console.WriteLine("Still Connected, but the Send would block"); 
                    connectState = true; } else { //Console.WriteLine("Disconnected: error code {0}!", e.NativeErrorCode); 
                    connectState = false; } } finally { tcpClient.Client.Blocking = blockingState; } //Console.WriteLine("Connected: {0}", client.Connected); 
            return connectState; #endregion } /// 斷線重連函數 ///   
        ///   
        private void Reconnect() { //IsconnectSuccess = false;
 tcpClient.Close(); streamToServer.Close(); //建立socket 
 SocketCreateConnect(); } private void Receive_Radar29() { buffer = new byte[BufferSize]; while (true) { try { if (!tcpClient.Client.Connected) { if (!IsSocketConnected()) { Reconnect(); return; } } streamToServer = tcpClient.GetStream(); int count = streamToServer.Read(buffer, 0, BufferSize); if (count == 0) { Reconnect(); return; } temp_buffer = new byte[count]; Array.Copy(buffer, 0, temp_buffer, 0, temp_buffer.Length); Array.Clear(buffer, 0, buffer.Length); List<byte[]> protocolList = requestHandler.GetActualProtocolByte(temp_buffer.ToList()); foreach (var item in protocolList) { Task.Factory.StartNew(ProcessProtocol, item); //ProcessProtocol(item);
 } } catch { //if (streamToServer != null) //{ // streamToServer.Close(); //} //tcpClient.Close(); //break;
                    continue; } } }