//from wp
function ajax(url, callbackFunction, params){
 
        var request = window.XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject("MSXML2.XMLHTTP.3.0");
 
        request.open("GET", url, true);
 
        request.onreadystatechange = function(){
 
                if (request.readyState == 4 && request.status == 200) {
                        	callbackFunction(request, params);
                }
        };
        request.send(null);
}