序列化反序列化通过套接字发送的消息时异常

Question

我正在创建一个程序，我正在尝试通过套接字系统连接服务器和多个客户端。由于某种原因，当我反序列化时，我得到了一个异常。

我这样做是为了使第一条消息的前 2 个字节包含即将收到的消息的长度。(这样我就可以接收比缓冲区(1024 字节(更大的消息(。我的错误可能与这段代码有关？

例外：

System.Runtime.Serialization.SerializationException： 'Binary stream "0"不包含有效的 BinaryHeader。可能的原因无效 序列化和 之间的流或对象版本更改 反序列化。

基本发送代码如下：

public void Send(byte[] data)
{
if (ClientSocket != null && ClientSocket.Connected)
{
ClientSocket.BeginSend(AddSize(data), 0, data.Length, 0, ResponseSend, this);
}
else
{
ConnectionFailed();
}
}
private byte[] AddSize(byte[] data)
{
var newData = BitConverter.GetBytes(Convert.ToUInt16(data.Length));
Array.Resize(ref newData, sizeof(ushort) + data.Length);
Array.Copy(data, 0, newData, sizeof(ushort), data.Length);
return newData;
}
private void ResponseSend(IAsyncResult ar)
{
try
{
// Complete sending the data to the remote device.  
var bytesSent = ClientSocket.EndSend(ar);
SendCompleted();
}
catch (SocketException ex)
{
ConnectionFailed();
}
}

基本接收代码如下：

private const int BufferSize = 1024;
// Receive buffer.  
private MemoryStream _bufferStream = new MemoryStream();
private readonly byte[] _buffer = new byte[BufferSize];
private ushort _messageLength;
public void Receive()
{
if (ClientSocket != null && ClientSocket.Connected)
{
ClientSocket.BeginReceive(_buffer, 0, BufferSize, SocketFlags.None, ReceiveCommand, this);
}
else
{
ConnectionFailed();
}
}
private void ReceiveCommand(IAsyncResult ar)
{
// Retrieve the socket from the state object.  
var client = (BaseClient)ar.AsyncState;
try
{
var bytesRead = ClientSocket.EndReceive(ar);
if (bytesRead <= 0)
{
ConnectionFailed();
return;
}
var messageSizeOffset = 0;
if (_messageLength == 0)
{
_messageLength = GetMessageLength(client._buffer);
messageSizeOffset = sizeof(ushort);
}
_bufferStream.Write(client._buffer, messageSizeOffset, bytesRead - messageSizeOffset);
if (_bufferStream.Length >= _messageLength)
{
var data = Deserialize(_bufferStream);
//Cleanup
_messageLength = 0;
_bufferStream.Dispose();
_bufferStream = new MemoryStream();
ReceiveCompleted(data);
}
Receive();
}
catch (SocketException ex)
{
ConnectionFailed();
}
}

我只使用这个简单的序列化和反序列化函数：

private byte[] Serialize(object item)
{
MemoryStream stream = new MemoryStream();
IFormatter formatter = new BinaryFormatter();
formatter.Serialize(stream, item);
return stream.ToArray();
}
public static object Deserialize(MemoryStream stream)
{
var binaryFormatter = new BinaryFormatter();
stream.Seek(0, SeekOrigin.Begin);
return binaryFormatter.Deserialize(stream);
}

有人知道为什么我会收到此错误吗？因为我已经毫无头绪了。

我还在以下链接中添加了一个示例：https://github.com/kevingoos/SocketTest

Answer 1

在Send：

public void Send(byte[] data)
{
if (ClientSocket != null && ClientSocket.Connected)
{
ClientSocket.BeginSend(AddSize(data), 0, data.Length, 0, ResponseSend, this);
}
else
{
ConnectionFailed();
}
}

您发送data.Length字节，但AddSize()方法在缓冲区的开头添加一个ushort消息长度字段。此字段的大小必须包含在发送的内容中。