c# - NetworkStream 从不写入数据

Question

好吧，所以我理解 TCP 是基于流而不是基于消息的整个想法 - 我不关心这个。

我想做的是简单地序列化一些东西，然后通过网络将它发送到另一个使用相同的基于消息的协议(protocol)的应用程序。

问题是，每当我序列化数据(我正在序列化为 XML)，然后将其写入网络流时，该死的东西永远不会写入它 - 永远不会。直到我关闭程序并关闭流，流才真正发送数据。到底发生了什么——TCP 是否在等待足够的数据发送？是不是在等我什么？ (我怀疑前者，因为我可以写简单的行，而它做得很好。)

这是我的客户的代码:

        TcpClient client = new TcpClient();
        client.Connect(IPAddress.Parse("127.0.0.1"), 10100);
        NetworkStream ns = client.GetStream();
        StreamWriter writer = new StreamWriter(ns);

        ListenerThread th = new ListenerThread(new StreamReader(ns));
        new Thread(th.run).Start();

        XmlSerializer serializer = new XmlSerializer(typeof(Message), new Type[] {typeof(AuthenticationMessage), typeof(ChangeChatRoomMessage), typeof(ChangePasswordMessage), typeof(ConnectionStatusMessage), typeof(InitializeMessage), typeof(StatusMessage), typeof(SuccessMessage), typeof(TextMessage)});

        string file =  "<some test xml file>";
        while(true)
        {
            FileStream stream = new FileStream(file, FileMode.Open, FileAccess.Read);
            StreamReader reader = new StreamReader(stream);
            Message newmsg = (Message)serializer.Deserialize(reader);
            stream.Close();

            serializer.Serialize(writer, newmsg);
            writer.Flush();

            file = Console.ReadLine();
        }

服务器代码如下:

    public void HandleMessage()
    {
        Message msg = (Message)serializer.Deserialize(reader);
        Console.WriteLine("Read Message " + msg.GetType());
    }

    public void Start()
    {
        while(true)
        {
            Socket socket = listener.AcceptSocket();
            NetworkStream stream = new NetworkStream(socket);
            reader = new StreamReader(stream);
            HandleMessage();
            stream.Close();
        }
    }

我的程序现在已经运行了 20 分钟，但没有向服务器发送任何内容。我尝试了所有我能想到的方法，刷新我的写入器缓冲区(TextWriter，显然不是 NetworkStream)，并将客户端设置为 NoDelay，等等……发生了什么，为什么？

Answer 1

Alright, so I understand the whole idea that TCP is stream based and not message based - I don't care about that.

其实这很重要，你应该关心它。向服务器发送数据时，您不仅应该尝试发送一些消息，还应该定义一些协议(protocol)(或使用现有协议(protocol)之一)，客户端在其中向服务器指示例如它打算发送多少数据。

下面是您如何继续的示例。在此示例中，客户端将总消息的长度作为前 4 个字节发送。

服务器:

class Program
{
    static void Main()
    {
        var listener = new TcpListener(new IPEndPoint(IPAddress.Loopback, 10100));
        listener.Start();
        while (true)
        {
            using (var client = listener.AcceptTcpClient())
            using (var stream = client.GetStream())
            using (var reader = new BinaryReader(stream))
            {
                // The first 4 bytes of the message will indicate
                // the total message length
                var length = reader.ReadInt32();
                var buffer = reader.ReadBytes(length);
                Console.WriteLine("Received {0} bytes from client:", length);
                Console.WriteLine("{0}", Encoding.UTF8.GetString(buffer));
            }
        }
    }
}

客户:

class Program
{
    static void Main()
    {
        using (var client = new TcpClient("127.0.0.1", 10100))
        using (var stream = client.GetStream())
        using (var writer = new BinaryWriter(stream))
        {
            var message = "<some test xml file>";
            var buffer = Encoding.UTF8.GetBytes(message);
            // Send the total message length in the first 4 bytes
            // so that the server knows how much it has to read
            writer.Write(buffer.Length);
            writer.Write(buffer);
            Console.WriteLine("Successfully sent {0} bytes to server", buffer.Length);
        }
    }
}