title: how do i prevent scroll down in javascript?
body: <p>ok... I might be a lazy one to search but it is a bit annoying that all I can find is</p>
  
  <p>"how can i set scroll down event" when I searched "how do i prevent scroll down". </p>
  
  <p>in my javascript code, I set event for down arrow key. When I press down arrow </p>
  
  <p>from the browser, the browser not only does an event I set, but also does</p>
  
  <p>scrolling down the page which is not I intended to. So here is my question. </p>
  
  <p>How can I disable scroll down function which occurs when I press down arrow?</p>
  
  <p>any help will be appreciated.</p>