二进制格式化从内存流冻结反序列化。

Question

我试图做一个客户端-服务器应用程序，通过套接字进行通信，他们的消息使用BinaryFormatter进行序列化和反序列化。我的代码冻结了，并且在达到反序列化时什么都不做，我不明白为什么，因为我没有异常。我也不能进入调试器，一切都冻结了。这是我的代码。

 public class Serializer
    {
        public static MemoryStream ToStream(object obj)
        {
            var stream = new MemoryStream();
            var formatter = new BinaryFormatter();
            formatter.Serialize(stream, obj);
            return stream;
        }

        public static object FromStream(MemoryStream stream)
        {
            Console.WriteLine("Starting from stream");
            var formatter = new BinaryFormatter();
            stream.Seek(0, SeekOrigin.Begin);
            object rez = formatter.Deserialize(stream); //NEVER GOES OVER THIS
            Console.WriteLine("Starting deserialization" + rez);
            return formatter.Deserialize(stream);
        }
    }

public class Connection
    {
        private Socket socket;
        public Connection(Socket socket)
        {
            this.socket = socket;
            Console.WriteLine($"Connected to client: {socket.RemoteEndPoint}");
            Task.Factory.StartNew(() => Execute(socket));
        }

        private void Execute(Socket socket)
        {
            while (true)
            {
                var buffer = new byte[2048];
                var bytesCount = socket.Receive(buffer);
                if(bytesCount != 0)
                {
                    var msgReceived = (Message)Serializer.FromStream(new MemoryStream(buffer, 0, buffer.Length));
                    Console.WriteLine($"Received msg: {msgReceived.Content}");
                }
               /* var msg = new Message { Content = "Hello World2!" };
                Console.WriteLine($"Sending msg with content: {msg.Content}");
                MemoryStream stream = Serializer.ToStream(msg);
                var bytesSent = socket.Send(stream.GetBuffer());*/

                Console.WriteLine("Trying again");
                Thread.Sleep(500);
            }
        }

客户端代码：

  var host = Dns.GetHostEntry("localhost");
            var ipAddress = host.AddressList.First();
            var serverEndpoint = new IPEndPoint(ipAddress, 9000);

            Socket serverSocket = new Socket(ipAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
            serverSocket.Connect(serverEndpoint);

            Console.WriteLine($"Successfully connected to server on: {serverSocket.RemoteEndPoint}");

            while (true)
            {
                var msg = new Message { Content = "Hello World!" };
                Console.WriteLine($"Sending msg with content: {msg.Content}");
                MemoryStream stream = Serializer.ToStream(msg);
                var bytesSent = serverSocket.Send(stream.GetBuffer());
                Console.WriteLine("Waiting to receive");

                var buffer = new byte[2048];
                int bytesReceived = serverSocket.Receive(buffer);
                if (bytesReceived != 0)
                {
                    var receivedMessage = (Message)Serializer.FromStream(new MemoryStream(buffer));
                    Console.WriteLine($"Received message: {receivedMessage.Content}");
                }

                Console.WriteLine("Received done");

            }

服务器代码:

var host = Dns.GetHostEntry("localhost");
            var ipAddress = host.AddressList.First();
            var localEndPoint = new IPEndPoint(ipAddress, 9000);
            var serverSocket = new Socket(ipAddress.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
            serverSocket.Bind(localEndPoint);
            serverSocket.Listen(1);

            while (true)
            {
                Console.WriteLine("Waiting for client");
                Socket clientSocket = serverSocket.Accept();
                var connection = new Connection(clientSocket);
            }

我还检查了字节数，它们正在到达服务器，缓冲区也不是空的，我不明白为什么deserialize什么都不做。

Answer 1

你调用了两次Deserialize，我认为这里有问题。

object rez = formatter.Deserialize(stream); //NEVER GOES OVER THIS
Console.WriteLine("Starting deserialization" + rez);
return formatter.Deserialize(stream);

我认为你可以使用这样的方法。

    private byte[] SerializeMessage(Message msg)
    {
        var formatter = new BinaryFormatter();
        byte[] buf;
        using (MemoryStream stream = new MemoryStream())
        {
            formatter.Serialize(stream, msg);
            buf = new byte[stream.Length];
            return stream.ToArray();
        }
    }

     private Message DeserializeMessage(byte[] buff)
     {
            var formatter = new BinaryFormatter();
            ConnectingMessage msg;
            using (Stream stream = new MemoryStream(buff))
            {
                msg = formatter.Deserialize(stream) as Message;
            }

            return msg;           
     }

另外，SendReceive方法是同步的，它们会阻止线程执行。

异步选项的描述在这里。https:/docs.microsoft.comen-usdotnetframeworknetwork-programmingusing-an-asynchronous-client-socket。

Answer 2

同时只能运行一段代码。当那个无限循环 while (true) 运行，其他代码将永远无法运行。

你需要在这个项目中添加一些多任务处理功能。最起码的量，这是每个文字处理器都需要的。然而你似乎也是在控制台中编程。根据我的经验，控制台和多任务处理并不能很好的结合起来。你需要在不阻止输入的情况下保持程序的活力。

我对学习多任务的建议是在Windows窗体中使用BackgroundWorker。BGW已经过时了，使用的是线程，在这里是不需要的，也不应该在生产性代码中使用。但它可能是我所知道的最好的多任务和线程的 "训练轮"。