[javascript] Scroll to the top of the page using JavaScript?

Active all Browser. Good luck

var process;
        var delay = 50; //milisecond scroll top
        var scrollPixel = 20; //pixel U want to change after milisecond
        //Fix Undefine pageofset when using IE 8 below;
        function getPapeYOfSet() {
            var yOfSet = (typeof (window.pageYOffset) === "number") ? window.pageYOffset : document.documentElement.scrollTop;
            return yOfSet;
        }



        function backToTop() {
            process = setInterval(function () {
                var yOfSet = getPapeYOfSet();
                if (yOfSet === 0) {
                    clearInterval(process);
                } else {
                    window.scrollBy(0, -scrollPixel);
                }
            }, delay);
        }