基于tcp的socket异步通信第二次服务端发送文件到客户端socket显示未连接

[qq_24062975]

我把代码贴出来，麻烦各位大神帮我看看问题出在哪里。

    private void OnStartServer()
        {
            try
            {
                //端口号
                IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, 50223);
                //监听
                socketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                socketWatch.Bind(endPoint);
                //一次性最多可监听500个客户端
                socketWatch.Listen(500);
                Console.WriteLine("服务端开始监听......");
                //创建用于和客户端通信的socket,第一个参数为委托类型
                socketWatch.BeginAccept(new AsyncCallback(AcceptInfo), socketWatch);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex);
            }
        }
        //关闭服务
        public void OnStop()
        {
            try
            {
                socketWatch.Shutdown(SocketShutdown.Both);
                socketWatch.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex);
            }
        }
        /// <summary>
        /// 等待客户端的连接，并且创建与之通信用的Socket
        /// </summary>
        /// <param name="aResult"></param>
        private void AcceptInfo(IAsyncResult aResult)
        {
            Socket socket = aResult.AsyncState as Socket;
            //创建与客户端通信的socket
            Socket client = socket.EndAccept(aResult);
            socketSend = client;
            //获取远程主机的终结点(ip+端口)
            string clientIp = ((System.Net.IPEndPoint)client.RemoteEndPoint).Address.ToString();
            string clientPort = ((System.Net.IPEndPoint)client.RemoteEndPoint).Port.ToString();
            Console.WriteLine("远程主机：" + clientIp + ":" + clientPort + "连接成功");
            try
            {
                //接收客户端消息
                client.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveAndSendMessage), client);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex);
            }
            //准备接受下一个客户端请求
            socket.BeginAccept(new AsyncCallback(AcceptInfo), socket);
        }

        private void ReceiveAndSendMessage(IAsyncResult aResult)
        {
            //接收客户端发来的消息
            Socket socket = aResult.AsyncState as Socket;
            try
            {
                //返回接收的数据的长度
                int strLength = 0;
             
                    strLength = socket.EndReceive(aResult);
                
                if (strLength == 0)
                {
                    socket.Shutdown(SocketShutdown.Both);
                    socket.Close();
                    return;
                }
                //将字节数组转换成字符串
                string strText = Encoding.UTF8.GetString(buffer, 0, strLength);
                Console.WriteLine("接收到的字符串：" + strText);
                //服务端给客户端发送图像，这里觉得应该优化下（在不开启线程的情况下测试下）
                if (strText == "2")
                {
                    //Thread sendThread = new Thread(SendFileToClient);
                    //sendThread.IsBackground = true;
                    //sendThread.Start(socket);
                    SendFileToClient(socket);
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex);
            }
            try
            {
                //接收客户端消息              
                socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveAndSendMessage), socket);
            }
            catch
            {
            }
        }
        /// <summary>
        /// 发送图像给客户端
        /// </summary>
        /// <param name="obj"></param>
        private void SendFileToClient(object obj)
        {
            Socket socket = obj as Socket;
            if (socket.Connected)
            {
                socket.BeginSend(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(SendFile), socket);
            }
            else
            {
                socket.Shutdown(SocketShutdown.Both);
                socket.Close();
            }
        }
        /// <summary>
        /// 发送
        /// </summary>
        /// <param name="aResult"></param>
        private void SendFile(IAsyncResult aResult)
        {
            Socket socket = aResult.AsyncState as Socket;
            //发送图像文件的路径                   
            //string filePath = @"D:\imagesTest";
            string filePath = @"D:\image";
            List<string> fileList = new List<string>();
            DirectoryInfo directoryInfo = new DirectoryInfo(filePath);
            FileStream fs = null;
            using (NetworkStream ns = new NetworkStream(socket, FileAccess.ReadWrite, false))
            {
                 
                foreach (FileInfo fileName in directoryInfo.GetFiles())
                {
                    try
                    {
                        string imagePath = null;
                        imagePath = filePath + "\\" + fileName.ToString();
                        fs = new FileStream(imagePath as string, FileMode.OpenOrCreate, FileAccess.Read, FileShare.ReadWrite);
                        //ns = new NetworkStream(socket, FileAccess.ReadWrite, false);
                        if (!File.Exists(imagePath.ToString()))
                            return;
                        byte[] fileBytes = null;
                        Int64 fileTotalLen = fs.Length + 132;
                        if (fileTotalLen <= maxBufferSize)//小文件发送
                        {
                            fileBytes = new byte[fileTotalLen];
                            Array.Copy(BitConverter.GetBytes(fileBytes.Length - 132), fileBytes, 4);
                            byte[] fileNameBytes = System.Text.Encoding.Default.GetBytes(fileName.ToString());
                            fileNameBytes.CopyTo(fileBytes, 4);
                            
                                using (fs)
                                {
                                    //将图片byte信息读入byte数组中
                                    fs.Read(fileBytes, 132, fileBytes.Length - 132);
                                    fs.Close();
                                }
                                IAsyncResult result = ns.BeginWrite(fileBytes, 0, fileBytes.Length, null, null);
                                ns.EndWrite(result);
                        }
                       
                                    ns.Flush();
                                
                            }
                            ns.Flush();
                        }

                    }
                    catch (Exception ex)
                    {
                      
                         
                        Console.WriteLine(ex);
                    }
                  
                  
                    fs.Close();
                }
                  //ns.Close();
               
            }
            int length = socket.EndSend(aResult);
            Console.WriteLine("完成消息发送...");
            
        }
    }