HTML元素：滚动条出现时得到通知

Question

I have a div like this:

<div id='test' style='overflow:auto'>
...
</div>

In javascript (no jquery) How do I know when - as a consequence of the user resizing the browser - the div is showing a horizontal bar or not ?

Note: I don't want only to figure if it is showing horizontal bar or not, I want to be notified when that happens.

Answer 1

If you want to hook the resize of window

window.onresize = function(){
 var test = document.getElementById("test");
 if(test.offsetHeight != test.scrollHeight)
    // raise event or call ur method
}