sergisergio / Ads

    var xobj = new XMLHttpRequest();

    xobj.overrideMimeType("application/json");

    xobj.open('GET', filename, true);

    xobj.onreadystatechange = function () {

        if (xobj.readyState == 4 && xobj.status == "200") {

            // Required use of an anonymous callback as .open will NOT return a value but simply returns undefined in asynchronous mode

            callback(xobj.responseText);

        }

    };

    xobj.send(null);

}