Question

I’ve got a weird problem with udp sockets. First of all, let me provide you with the code:

Server side:

        UdpClient udpClient = new UdpClient(UdpPort);

        udpClient.Connect(pendingClient.IpEndPoint, pendingClient.UdpPort);

        foreach (int frameNumber in pendingClient.FramesToSend)
        {
            byte[] frameBytes = ...
            udpClient.Send(frameBytes, frameBytes.Length);
        }
        udpClient.Close();

Client side:

 using (Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp))
        {
            socket.Bind(new IPEndPoint(IPAddress.Any, UdpPort));

            socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, 1000);

            Console.WriteLine("Receiving frames");
            while (!_sendingCompleted)
            {
                byte[] receive = new byte[Constants.FrameSize + Frame.HeaderSizeBytes];
                try
                {
                    socket.Receive(receive);
                }
                catch (SocketException exception)
                {
                    if (exception.SocketErrorCode == SocketError.TimedOut)
                    {
                        break;
                    }

                    throw;
                }
           ...
}

The problem is: when I do sending from server to client first time everything works perfectly, but when I do it second ( and so on) time – client receives nothing. What can be a reason of that problem and how could I solve it?

Many thanks.

Answer 1

Looks like you are not receiving data in the cycle, try the following approach:

do 
{

  bytes = s.Receive(bytesReceived, bytesReceived.Length, 0);

  page = page + Encoding.ASCII.GetString(bytesReceived, 0, bytes);

} while (bytes > 0);