Scrollbar location within a UL

I've looked at other questions but I can't seem to find an answer...

if($("#my-list").pageYOffset > 541){
$("#my-list").scrollTo("-=540px");
}

This is my code. As you can see, I'm trying to use jQuery or just some JavaScript to identify where I've scrolled to i开发者_开发知识库n my unordered list (which has a vertical scroll due to overflow:scroll). If this target offset meets a certain threshold, I want it to bump back up to the beginning.

Any help would be much appreciated. Thank you.

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Well, pageYOffset gives how far the entire page has been scrolled, but as far as I understand you want to observe the scrolltop offset of #my-list's children (i.e. li) relative to their parent (i.e. the ul). So the function would have to look something like

$("#my-list").scroll(function() {
    if($(this).scrollTop()>541) {
         $(this).scrollTop("0px");   
    }
});

For a working example look at http://jsfiddle.net/LFE2v/