function scrollTo(element, to, duration) {
if (duration <= 0) return;
var difference = to - element.scrollTop;
var perTick = difference / duration * 10;
setTimeout(function() {
element.scrollTop = element.scrollTop + perTick;
if (element.scrollTop === to) return;
scrollTo(element, to, duration - 10);
}, 10);
}
Demo:
function runScroll() {
scrollTo(document.body, 0, 600);
}
var scrollme;
scrollme = document.querySelector("#scrollme");
scrollme.addEventListener("click",runScroll,false)
function scrollTo(element, to, duration) {
if (duration <= 0) return;
var difference = to - element.scrollTop;
var perTick = difference / duration * 10;
setTimeout(function() {
element.scrollTop = element.scrollTop + perTick;
if (element.scrollTop == to) return;
scrollTo(element, to, duration - 10);
}, 10);
}
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</p>
<button id=scrollme type="button">To the top</button>