Socket communication does not transmit full string

Question

I am using the code below to read a (quite lengthy) string of data separated by newlines sent from a mobile phone via a TCP socket. I am never able to receive the full string. I have never overrun the buffer. Any advice?

public class aClass

{
    Socket mainSocket;
    List<Socket> socketList;
    int port = 8000;

	public aClass()
	{
        mainSocket = new Socket(AddressFamily.Unspecified, SocketType.Stream, ProtocolType.Tcp);
        IPEndPoint local = new IPEndPoint(IPAddress.Any, port);
        socketList = new List<Socket>();
        mainSocket.Bind(local);
        mainSocket.Listen(4);
        mainSocket.BeginAccept(new AsyncCallback(endConnect), null);
	}

    private void endConnect(IAsyncResult ar)
    {
        
        Socket newSocket = mainSocket.EndAccept(ar);
        beginListen(newSocket);
        socketList.Add(newSocket);
    }

    // Class obtained from Jayan Nair
    public class SocketPacket
    {
        public System.Net.Sockets.Socket m_currentSocket;
        public byte[] dataBuffer = new byte[2048];
    }

    private void beginListen(Socket theSocket)
    {

        SocketPacket sp = new SocketPacket();
        sp.m_currentSocket = theSocket;
        theSocket.BeginReceive(sp.dataBuffer, 0, sp.dataBuffer.Length, SocketFlags.None,
             new AsyncCallback(onReceive), sp);
    }

    private void onReceive(IAsyncResult ar)
    {
        SocketPacket socketData = (SocketPacket)ar.AsyncState;
        Socket theSocket = socketData.m_currentSocket;
        int nBytes = theSocket.EndReceive(ar);
        if (nBytes > 0)
        {
            String dataStr = Encoding.ASCII.GetString(socketData.dataBuffer, 2, nBytes);
            if (dataStr.Contains("over"))
            {
                disconnect(theSocket);
            }
            else
            {
                parse(dataStr);
                beginListen(theSocket);
            }
        }
    }
    private void disconnect (Socket theSocket)
    {
	// To be written
    }
}

Answer 1

You need message framing: http://nitoprograms.blogspot.com/2009/04/message-framing.html

       -Steve

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Programming blog: http://nitoprograms.blogspot.com/
  Including my TCP/IP .NET Sockets FAQ

Microsoft Certified Professional Developer