Programming Discussion Thread

[DacoTaco]

(10-30-2015, 09:54 PM)ExtremeDude2 Wrote: Uh oh, I'm doing a networking project in C#

then take a look at this on how i fixed it, incase you stumble upon the same issue

i had the issue when i dc'd the client in the middle of my protocol's handshake. only on the 2nd network action the server was like "wait a minute..."

Code:

static public int SendData(ref byte[] buffer, ref Socket socket)
        {
            return SendData(ref buffer, 0, ref socket);
        }
        static public int SendData(ref byte[] buffer, int size, ref Socket socket)
        {
            if (buffer == null || socket == null)
                return -1;

            int ret = 0;

            if (CheckConnection(ref socket))
            {
                if (size == 0)
                {
                    ret = socket.Send(buffer);
                }
                else
                    ret = socket.Send(buffer, size, 0);
            }
            else
                ret = -2;
            return ret;
        }
        static public bool CheckConnection(ref Socket socket)
        {
            if (socket == null)
                return false;

            try
            {
                //if the socket says connected we test it to check if its true or not. C# likes saying its connected while its not it seems...
                //if it says not connected then its clearly not connected
                if (socket.Connected)
                {
                    //poll the connection. the poll will return true if :
                    // - a connection is pending
                    // - data is available for reading
                    // - connection is closed or unavailable
                    //
                    // so if it returns false, the connection is there but nothing can be read
                    // if its true, we need to check if we can read data. if we can't, its either pending (useless) or closed (even more useless)
                    // so we mark it as closed.
                    bool bpoll = false;
                    bpoll = socket.Poll(0, SelectMode.SelectRead);
                    if (bpoll)
                    {
                        byte[] buff = new byte[1];
                        int recv_value = socket.Receive(buff, SocketFlags.Peek);
                        if (recv_value <= 0)
                        {
                            // Client disconnected
                            return false;
                        }
                    }
                }
                else
                    return false;

            }
            catch (SocketException ex)
            {
                //something went wrong. im guessing connection is closed but meh. lets just assume connection is a no go
                return false;
            }
            return true;
        }