C# socket ir learn

I just received my iTach WF2IR and am playing around a bit in C#, currently I am focusing on writing some code to learn IR codes from my remotes. It seems to work, even though I'm no expert on socket programming. I did notice something I wasn't expecting, perhaps I'm approaching this in the wrong way. Let me explain.... I read in the documentation that the iTach sends learnt codes to the connection that sent the "get_IRL" command. So I assume that I need to make use of an asynchronous connection..

I have something like this on winform:

private Socket _client;

private void Connect_Click(object sender, EventArgs e)

{
            Socket newsock = new Socket(AddressFamily.InterNetwork,
                            SocketType.Stream, ProtocolType.Tcp);
            IPEndPoint iep = new IPEndPoint(IPAddress.Parse("192.168.0.103"), 4998);
            newsock.BeginConnect(iep, new AsyncCallback(Connected), newsock);
}

void Connected(IAsyncResult iar)
        {
            _client = (Socket)iar.AsyncState;
            try
            {
                _client.EndConnect(iar);
                Console.WriteLine("Connected to", _client.RemoteEndPoint.ToString());

                _client.BeginReceive(data, 0, size, SocketFlags.None,new AsyncCallback(ReceiveData), _client);
            }
            catch (SocketException se)
            {
                Console.WriteLine("Error connecting: ", se.Message);
            }
        }

In the Connected delegate I call the BeginReceive method where the ReceiveData delegate is passed the the AsyncCallback...

The I send a "get_IRL" command to the iTach and the first response that I get in the ReceiveData method (euhm delegate) is IR Learner Enabled↵

The ReceiveData delegate looks like this

}

If I leave it like this then I will not receive any further messages from the iTach, I need to tell the socket to "BeginReceive" again, calling the same delage again.

}

When I now send IR commands from my remote to the iTach I receive them, but the funny thing is that it is always in 4 separate messages (packets?). Is this expected behaviour, or is the code I've written not 100% correct?

Now I parse the response I get from the iTach to see whether the message I'm receiving is some sort of response from a command or part of a "learning session". And since I noticed a learning session goes in 4 messages I also have a counter... Here's the complete code.. My question is the following, am I approaching this in the correct way, or should I do it differently?

void ReceiveData(IAsyncResult iar)
        {
            Socket remote = (Socket)iar.AsyncState;
            int recv = remote.EndReceive(iar);
            string stringData = Encoding.ASCII.GetString(data, 0, recv);

            Console.WriteLine("Receive Data: " + stringData);

            remote.BeginReceive(data, 0, size, SocketFlags.None, new AsyncCallback(ReceiveData), remote);

            if (String.Compare(stringData, "sendir") > 0)
            {
                _learningcounter = 1;
                _learnmessage = stringData;
            }
            else if (_learningcounter < 4)
            {
                _learnmessage = _learnmessage + stringData;
                _learningcounter++;
            }
            else
            {
                _learnmessage = "";
                _learningcounter = 0;
            }

            if (_learningcounter == 4)
            {
                Console.WriteLine("_learnmessage: " + _learnmessage);
            }

            remote.BeginReceive(data, 0, size, SocketFlags.None, new AsyncCallback(ReceiveData), remote);

        }

Josh Sherman January 19, 2012 20:23

It looks like what you are doing here will work without issue, but there is a problem that could arise. Codes will likely come in multiple packets, but the amount of packets is not defined. Were you to hold down your button for longer, you would likely get more packets than you are currently getting. The best way to handle this is to look for the delimiter that terminates our captured IR commands, which is a carriage return and line feed "0x0D0A". This will guarantee that the command is finished and that any alteration you plan to do with the string can be done. Feel free to let us know if you have any difficulties getting this working.

C# socket ir learn

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