How to determine scroll direction without actually scrolling

Question

I am coding a page where the first time the user scrolls, it doesn\'t actually scroll the page down, instead it adds a class with a transition. I\'d like to detect when the

Answer 1

I know this post is from 5 years ago but I didn't see any good Jquery answer (the .on('mousewheel') doesn't work for me...)

Simple answer with jquery, and use window instead of body to be sure you are taking scroll event :

$(window).on('wheel', function(e) {
    var scroll = e.originalEvent.deltaY < 0 ? 'up' : 'down';
    console.log(scroll);
});