Socket.io how to check if user is typing and broadcast it to other users

Question

I am trying to setup socket.io chat server. I have gotten it up to send and receive message from server and client. I was interested in showing users if some one is typing. I kn

Answer 1

Just thought I'd add my variation on the very helpful answer given by abject_error. This allows for the status of typing as well as stopped typing but message was entered. I'm not using socket.io but you get the idea.

var typingStatus=0; //0=Not typing: message blank, 1=typing, 2=typing: something there
var typingStatus_timeout = undefined;

//called when timeout kicks in that we've stopped typing
function function_typingStatus_timeout(){
    //message entered
    if ($('#chat_message').val().trim()) {
        typingStatus=2;
    //message is blank
    } else {
        typingStatus=0;
    }
    //send new status
    connection.send(JSON.stringify({
        action:'typingStatus',
        typingStatus:typingStatus,
    }));
}

$(document).ready(function(){
    //TYPING
    $('#chat_message').keydown(function(e) {
        //only record typing if enter not pressed
        if(e.which!=13 && e.keyCode!=13) {
            //weren't typing before but are now
            if (typingStatus!=1) {
                //switch to 1 for in progress
                typingStatus=1;
                //broadcast
                connection.send(JSON.stringify({
                    action:'typingStatus',
                    typingStatus:typingStatus,
                }));        
            //were typing before and still are, clear the timeout, we're going to reset it in the next step
            } else {
                clearTimeout(typingStatus_timeout);
            }
            //either way, set the timeout to trigger after a second of not typing
            typingStatus_timeout=setTimeout(function_typingStatus_timeout,1000);

        //if enter was pressed we want to not have it register as a keydown at all.  there's a separate function on keyup that looks for enter being pressed and sends the message
        } else {
            e.preventDefault();
        }
    });
});