TCP客户端在被服务器断开之前一直处于停滞状态

Question

print("TCP -> Data received:\n" + file + "\n\n" + totalrecbytes + " Bytes");

while ((recBytes = netstream.Read(bytes, 0, bytes.Length)) > 0)

print("TCP -> Data received:\n" + file + "\n\n" + totalrecbytes + " Bytes");

private Thread _tcpThread;
private TcpClient _socketConnection;

public void Connect()
{
    try
    {
        _tcpThread = new Thread(ReciveDataClient);
        _tcpThread.IsBackground = true;
        _tcpThread.Start();
    }
    catch (Exception e)
    {
        print(e.Message);
    }
}

private void ReciveDataClient()
{
    try
    {
        _socketConnection = new TcpClient("xxx.xxx.xxx.xxx", 54321);
        print(this, "TCP -> Connection Success!");
    }
    catch (Exception e)
    {
        print("connection error: " + e.Message)
        return;
    }

    try
    {
        var bytes = new byte[BUFFER_SIZE];

        while (_socketConnection.Connected)
        {
            if (_socketConnection.Available <= 0) continue;

            // Get a stream object for reading              
            var netstream = _socketConnection.GetStream();

            int totalrecbytes = 0;

            int recBytes;
            string file = "";

            // Read incomming stream into byte arrary.                  
            while ((recBytes = netstream.Read(bytes, 0, bytes.Length)) > 0)
            {
                var incommingData = new byte[recBytes];
                Array.Copy(bytes, 0, incommingData, 0, recBytes);
                // Convert byte array to string message.                        
                var serverMessage = Encoding.ASCII.GetString(incommingData);
                file += serverMessage;
                totalrecbytes += recBytes;
            }

            print("TCP -> Data received:\n" + file + "\n\n" + totalrecbytes + " Bytes");

            netstream.Close();
        }

        print("TCP -> connection was terminated by the server");
    }
    catch (Exception e)
    {
        print(e.Message)
        return;
    }
}

到目前为止，我能找到的唯一解决办法是在发送数据后总是断开与服务器端的连接，并且在我的代码中，将整个receivedataclient包装在一个while循环中，类似于

private void ReciveDataClient()
{
    while (true)
    {
        try
        {
            _socketConnection = new TcpClient(_server.ToString(), _server.Port);

            //...

以便在服务器发送一些数据并断开客户端连接后立即启动新的连接。

Answer 1

多亏了达米恩这个不信的人和身临其境的人的帮助，我才弄明白了这一点。经常阅读文档确实很有帮助，特别是当您是第一次使用时^^

networkstream.read是一个阻塞调用，如文档所述

返回：从NetworkStream读取的字节数，如果套接字已关闭，则返回0。

private Thread _tcpThread;
private TcpClient _socketConnection;

public void Connect()
{
    if(_socketConnection != null) return;

    try
    {
        _tcpThread = new Thread(ReciveDataClient);
        _tcpThread.IsBackground = true;
        _tcpThread.Start();
    }
    catch (Exception e)
    {
        print("TCP -> Thread error: " + e.Message);
    }
}

public void Disconnect()
{
    if(_socketConnection = null) return;

    _tcpThread.Abort();
}

private void ReciveDataClient()
{
    try
    {
        _socketConnection = new TcpClient("xxx.xxx.xxx.xxx", 54321);
        print(this, "TCP -> Connection Success!");
    }
    catch (Exception e)
    {
        print("TCP -> connection error: " + e.Message)
        return;
    }

    try
    {
        while(true)
        {
            // Get a stream object for reading              
            var netstream = _socketConnection.GetStream();

            //Check if still connected                
            if(_socketConnection.Client.Poll(0, SelectMode.SelectRead))
            {
                byte[] buff = new byte[1];
                if( _socketConnection.Client.Receive( buff, SocketFlags.Peek ) == 0 )
                {
                    // Server disconnected or connection lost
                    break;
                }
            }

            // Check to see if this NetworkStream is readable.
            if(myNetworkStream.CanRead)
            {
                byte[] myReadBuffer = new byte[BUFFER_SIZE];
                StringBuilder myCompleteMessage = new StringBuilder();
                int numberOfBytesRead = 0;
                int totalBytesReceived = 0;

                // Incoming message may be larger than the buffer size.
                do
                {
                    numberOfBytesRead = myNetworkStream.Read(myReadBuffer, 0, myReadBuffer.Length);
                    myCompleteMessage.AppendFormat("{0}", Encoding.ASCII.GetString(myReadBuffer, 0, numberOfBytesRead));    
                    totalBytesReceived += numberOfBytesRead;        
                }
                while(myNetworkStream.DataAvailable);

                // Print out the received message to the console.
                print("TCP -> Data received:\n" + myCompleteMessage.ToString() + "\n\n" + totalrecbytes + " Bytes");
            }
            else
            {
                //Prevent a direct loop
                Thread.Sleep(100);
            }          
        }

        print("TCP -> connection was terminated by the server");
    }
    catch(ThreadAbortException)
    {
        print("TCP -> Disconnected");
    }
    catch(Exception e)
    {
        print(e.Message)
    }

    // Clean up
    _socketConnection?.Close();
    _socketConnection?.Dispose();
    _socketConnection = null;
}