通过TCP发送大对象:“解析完成之前遇到的流结束”

时间:2010-08-30 22:35:01

标签: c# serialization tcp tcpclient

每当我尝试从SerializationException反序列化双打列表时,我都会收到NetworkStream

  

之前遇到的流结束   解析完成了

我有一个简单的客户端服务器架构:我的TcpTransportClient包含了TcpClient的功能,我使用了两种基本方法:Send(发送消息)和Receive (阻止直到收到消息)。

Send函数需要Message,使用BinaryFormatter对其进行序列化,并通过NetworkStream发送字节。

public void Send(Message message)
{
    if (message == null)
    {
        throw new TransportException("Invalidate Parameter In Send Call");
    }

    if (_tcpClient == null || !_tcpClient.Connected)
    {
        throw new TransportException("Client Not Connected");
    }

    lock (_sync)
    {
        // Serialzie the message
        MemoryStream memStream = new MemoryStream();
        _serializer.Serialize(memStream, message);

        // Get the bytes of of the memory stream
        byte[] buffer = memStream.GetBuffer();

        // Write the message to the network stream
        NetworkStream networkStream = _tcpClient.GetStream();
        networkStream.Write(buffer, 0, buffer.Length);
        networkStream.Flush();
    }
}

接收函数从NetworkStream将字节读入缓冲区,然后使用BinaryFormatter反序列化消息:

public Message Receive()
{
    if (_tcpClient == null || !_tcpClient.Connected)
    {
        throw new TransportException("Client Not Connected");
    }

    byte[] buffer;
    MemoryStream memStream = new MemoryStream();
    NetworkStream netStream = _tcpClient.GetStream();
    try
    {
        do
        {
            // Allocate a new buffer
            buffer = new byte[_tcpClient.ReceiveBufferSize];

            // Read the message buffer
            int sizeRead = netStream.Read(buffer, 0, buffer.Length);

            // Write the buffer to the memory stream
            memStream.Write(buffer, 0, sizeRead);

        } while (netStream.DataAvailable);

        // Reset the memory stream position
        memStream.Position = 0;

        // Deserialize the message
        object tmp = _deserializer.Deserialize(memStream); // <-- The exception is here!

        // Cast the object to a message
        return (Message)tmp;
    }
    catch (System.Exception e)
    {
        if (_tcpClient == null || !_tcpClient.Connected)
        {
            throw new TransportException("Client Not Connected");
        }
        else
        {
            throw e;
        }
    }
}

我有一个基本的发送线程:

TcpTransportClient client = new TcpTransportClient(GetLocalAddress(), servicePort);
client.Connect();

Thread sendThread = new Thread(() =>
{
    List<double> dataSet = new List<double>();
    for (double d = 0.0; d < 500.0; d++)
    {
        dataSet.Add(d);
    }

    while (true)
    {
        try
        {
            // Serialize the data set
            MemoryStream memStream = new MemoryStream();
            BinaryFormatter binFormat = new BinaryFormatter();
            binFormat.Serialize(memStream, (object)dataSet);

            // Create a message
            Message msg = new Message();

            // Hold the object bytes in an opaque field
            msg.SetFieldValue(1000, memStream.GetBuffer());

            // Set the message topic
            msg.SetTopic("client.dataSet");

            // Send the message
            client.Send(msg);

            // Sleep
            Thread.Sleep(3000);
        }
        catch (TransportException)
        {
            break;
        }
        catch(Exception)
        {
            //ignore it
        }
    }
});
sendThread.IsBackground = true;
sendThread.Start();

接收线程,只要接受TcpClient就会启动:

public void HandleAcceptedClient(TcpTransportClient client)
{
    Thread receiveThread = new Thread(() =>
    {
        while (true)
        {
            try
            {
                Message msg = client.Receive();
                Trace.WriteLine("Server Received: " + msg.GetTopic());
                byte[] buffer = msg.GetFieldOpaqueValue(1000);
                MemoryStream memStream = new MemoryStream(buffer);
                BinaryFormatter binFormat = new BinaryFormatter();

                List<double> dataSet = (List<double>)binFormat.Deserialize(memStream);
                if (dataSet.Count == 500)
                {
                    Trace.WriteLine(DateTime.Now + ": OK");
                }
                else
                {
                    Trace.WriteLine(DateTime.Now + ": FAIL");
                }
            }
            catch (TransportException)
            {
                break;
            }
            catch(Exception)
            {
                // ignore it
            }

        }

    });
    receiveThread.IsBackground = true;
    receiveThread.Start();
}

当我尝试在Receive的{​​{1}}方法中反序列化消息时,总会发生异常,但只有在数据集中放入一些数据时才会出现问题。通过网络发送值列表并在接收端成功反序列化的正确方法是什么?

P.S。我在nearly identical question中尝试了解决方案,但它没有用:我仍然得到相同的例外。

2 个答案:

答案 0 :(得分:4)

  

while(netStream.DataAvailable);

这不正确。当Read()调用返回0时,您应该停止读取.DataAvailable属性只是告诉您Read()调用是否会阻塞,等待允许服务器赶上。

答案 1 :(得分:4)

您需要message framing