0

I am using:

window.addEventListener('scroll', async() => {

})

How to determine if the user is scrolling upwards or downwards in JavaScript.

Brian Tompsett - 汤莱恩
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khan
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  • This [post](https://stackoverflow.com/a/31223774/11908502) should help you. – SMAKSS Apr 01 '20 at 17:03
  • 2
    I think this question has been answered here: https://stackoverflow.com/questions/31223341/detecting-scroll-direction – imadu Apr 01 '20 at 17:05
  • 1
    Does this answer your question? [Detecting scroll direction](https://stackoverflow.com/questions/31223341/detecting-scroll-direction) – Chunky Chunk Apr 01 '20 at 17:27

1 Answers1

0

I would suggest getting the scrollPosition before the eventListener, and then see if it is greater or less than the current scroll position. Then you will be able to see if the user has scrolled up or down.

let scrollBefore = window.scrollY;
window.addEventListener("scroll", () => {
  if (scrollBefore > window.scrollY) {
    console.log("scroll up")
  } else {
    console.log("scroll down")
  }
  scrollBefore = window.scrollY;
});
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Brayden W
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