how to detect window scroll px javascrip code example

Example 1: how to know how many pixels of page be scrolled javascript

window.onscroll = function (e) {
    console.log(window.scrollY); // Value of scroll Y in px
};

Example 2: how to know how many pixels of page be scrolled javascript

$(window).scroll(function() {
     // use the value from $(window).scrollTop(); 
 });