How can I know in Java script the page scrollUp or down

Question

Javascript

Answer 1

https://www.google.com/url?sa=t&source=web&rct=j&url=https://stackoverflow.com/questions/31223341/detecting-scroll-direction&ved=2ahUKEwiP_NOrlr_tAhXNYcAKHSF_D_UQFjAAegQIAxAC&usg=AOvVaw1pAid-sbwlMnvHDGynPt4y

Answer 2

Take window.pageYOffset before scrolling happens and after scrolling happened
Substract after from before .. if negative, the scroll direction is up, if positive it's down

Answer 3

You will use window.onscroll() event to detect scrolling and take to the scroll positions before and after

Answer 4

How can I know in Java script the page scrollUp or down