js get scroll position of document code example

Example 1: javascript get scroll position

function getYPosition(){
  var top  = window.pageYOffset || document.documentElement.scrollTop
  return top;
}

Example 2: scroll position

$(window).scroll(function() {
	var $height = $(window).scrollTop();
  if($height > 50) {
		//do something
	} else {
		//do something
	}
});