Detect div scroll bar hit the top

Question

how to detect when div scroll bar, scroll up and hit the top(only when it hit the top)

I have found another post, but this one is hit the bottom.

what i need is hit the top. anyone know how to change this?

$("#divID").scroll(function(){
    if($(this)[0].scrollHeight - $(this).scrollTop() <= $(this).outerHeight())
    {
        alert(1);
    }
});

Know when vertical scrollbar hits bottom of scroll in div

Answer 1

working fiddle

var el = $('.test');
el.on('scroll', function(){

    if(el.scrollTop() == 0){alert("i just hit the top")}


});