Frustrating TCP Serialization Exception: Binary stream '0' does not contain a valid BinaryHeader
I posted a question on how to send large objects over TCP and it seems like the primary issue is solved, but now frequently I get another exception:
Binary stream '0' does not contain a valid BinaryHeader. Possible causes are invalid stream or object version c开发者_StackOverflowhange between serialization and deserialization.
The issue is still in my Receive method:
public Message Receive()
{
if (_tcpClient == null || !_tcpClient.Connected)
{
throw new TransportException("Client Not Connected");
}
// buffers
byte[] msgBuffer;
byte[] sizeBuffer = new byte[sizeof(int)];
// bites read
int readSize = 0;
// message size
int size = 0;
MemoryStream memStream = new MemoryStream();
NetworkStream netStream = _tcpClient.GetStream();
BinaryFormatter formatter = new BinaryFormatter();
try
{
// Read the message length
netStream.Read(sizeBuffer, 0, sizeof(int));
// Extract the message length
size = BitConverter.ToInt32(sizeBuffer, 0);
msgBuffer = new byte[size];
// Fill up the message msgBuffer
do
{
// Clear the buffer
Array.Clear(msgBuffer, 0, size);
// Read the message
readSize += netStream.Read(msgBuffer, 0, _tcpClient.ReceiveBufferSize);
// Write the msgBuffer to the memory streamvb
memStream.Write(msgBuffer, 0, readSize);
} while (readSize < size);
// Reset the memory stream position
memStream.Position = 0;
// Deserialize the message
return (Message)formatter.Deserialize(memStream); // <-- Exception here
}
catch (System.Exception e)
{
if (_tcpClient == null || !_tcpClient.Connected)
{
throw new TransportException("Client Not Connected");
}
else
{
throw e;
}
}
}
The rest of the code relevant to this example can be found in my original question.
Does anybody know what is causing this exception and how I can avoid it?
Update
Changed the Read
to read a maximum of _tcpClient.ReceiveBufferSize
bytes at a time, rather than trying to read the full message size (which can be larger than the buffer size) and while the frequency of the Exception decreased slightly, it's still occurring quite often.
Let me suggest you a slight simplification of your code:
public Message Receive()
{
try
{
if (_tcpClient == null || !_tcpClient.Connected)
{
throw new TransportException("Client Not Connected");
}
using (var stream = _tcpClient.GetStream())
using (var reader = new BinaryReader(stream))
{
int size = reader.ReadInt32();
byte[] buffer = reader.ReadBytes(size);
using (var memStream = new MemoryStream(buffer))
{
var formatter = new BinaryFormatter();
return (Message)formatter.Deserialize(memStream);
}
}
}
catch (System.Exception e)
{
if (_tcpClient == null || !_tcpClient.Connected)
{
throw new TransportException("Client Not Connected");
}
throw e;
}
}
Also if you are doing this for fun and/or education purposes then it's ok, but in a real project you should probably consider WCF in order to transmit objects over the wire.
WCF not so good in client-server. Th polling duplex is quite raw technology.
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