Chatroom Javascript

function getChat(id){
    //alert("test");
    $.ajax({url: "chatroomlistener.php"}).done(function(msg) {
        //alert(msg);
        $('#' + id).html(msg);
    });

}

function sendChat(){

    var chat = document.getElementById("chat").value;
    var name = document.getElementById("name").value;

    var formdata = {chat : chat, name: name};

    $.ajax({
        url: "chatroomlistener.php",
        type: "post",
        data: formdata
    });

    document.getElementById("chat").value = '';

}