if window scroll javascript code example
Example 1: window.scroll
scroll function
window.scroll({
top: 0,
left: 0,
behavior: 'smooth'
});
window.scroll(x-coord, y-coord)
window.scroll(options)
Example 2: javascript scroll privent
// left: 37, up: 38, right: 39, down: 40,
// spacebar: 32, pageup: 33, pagedown: 34, end: 35, home: 36
var keys = {37: 1, 38: 1, 39: 1, 40: 1};
function preventDefault(e) {
e.preventDefault();
}
function preventDefaultForScrollKeys(e) {
if (keys[e.keyCode]) {
preventDefault(e);
return false;
}
}
// modern Chrome requires { passive: false } when adding event
var supportsPassive = false;
try {
window.addEventListener("test", null, Object.defineProperty({}, 'passive', {
get: function () { supportsPassive = true; }
}));
} catch(e) {}
var wheelOpt = supportsPassive ? { passive: false } : false;
var wheelEvent = 'onwheel' in document.createElement('div') ? 'wheel' : 'mousewheel';
// call this to Disable
function disableScroll() {
window.addEventListener('DOMMouseScroll', preventDefault, false); // older FF
window.addEventListener(wheelEvent, preventDefault, wheelOpt); // modern desktop
window.addEventListener('touchmove', preventDefault, wheelOpt); // mobile
window.addEventListener('keydown', preventDefaultForScrollKeys, false);
}
// call this to Enable
function enableScroll() {
window.removeEventListener('DOMMouseScroll', preventDefault, false);
window.removeEventListener(wheelEvent, preventDefault, wheelOpt);
window.removeEventListener('touchmove', preventDefault, wheelOpt);
window.removeEventListener('keydown', preventDefaultForScrollKeys, false);
}
Example 3: js detect scroll
window.onscroll = function (e) {
// called when the window is scrolled.
}