4:19:50 - 4:36:29 User-Triggered Messaging In this task, users are to create a simple form to receive input from the user. This input is then sent to the server through Socket.io and displayed for all connected clients. Kyle also shows how to emit messages only to the other clients connected and not to the sender.send and receive websocket messages on the client

on the client

  document.getElementById("sendbutton").addEventListener("click", function(evt){
    var msg = document.getElementById("typeit").value;
    if (msg) {
        socket.emit("typeit",msg);
        document.getElementById("messagebox").innerHTML += msg + "<br>";
        document.getElementById("typeit").value = "";
    }
});

to receive messages:

  socket.on("messages", function(msg){
    document.getElementById("messagebox").innerHTML += msg + "<br>";
});

on the server (see note: Making a Socket Connection)

  io.on("connection",handleIO);

function handleIO(socket) {
    // ... (handle disconnect, etc)

	function getmsg(msg) {
		io.sockets.emit("broadcast",msg);
	}


	socket.on("msg",getmsg);

}

  io.on("connection",handleIO);

function handleIO(socket) {
    // ... (handle disconnect, etc)
	socket.on("typeit",function(msg){
	    socket.broadcast.emit("messages", msg);
	});
}

with the ​socket.broadcast​ you will only send to message to everyone else but the client who sent the message. (​socket​ has been passed to ​handleIO​ as a connection parameter)latency is about 50 to 100ms