Capturing Scroll Event

Use the addEventListener method on the window object. Example:

window.addEventListener("scroll", function() {
	 var msg = 'html.scrolltop is ' + document.getElementsByTagName('html')[0].scrollTop + '<br>';
	 msg += 'body.scrolltop is ' + document.body.scrollTop + '<br>';
	 msg += 'pageYOffset is ' + window.pageYOffset + '<br>';
	 document.getElementById('debug').innerHTML = msg;
});

Getting the Scroll Position

jQuery is useful to abstract away the browser differences, but if you want a pure Javascript way, and you don’t need to support IE8 or older, then this works:

var currentScrollAmount = window.pageYOffset

Demo