How to get maximum document scrolltop value

Question

I am making some plugin and I need to get maximum scrollTop value of the document. Maximum scrollTop value is 2001 , but $(docum

Answer 1

If you want to "guess" the maximum scrolltop value, maybe you should compare the height of the document and the viewport height (size of your window).

/**
 * Return a viewport object (width and height)
 */
function viewport()
{
    var e = window, a = 'inner';
    if (!('innerWidth' in window))
    {
        a = 'client';
        e = document.documentElement || document.body;
    }
    return { width : e[ a+'Width' ] , height : e[ a+'Height' ] }
}

// Retrieve the height of the document, including padding, margin and border
var documentHeight = $(document).outerheight(true);
var viewPortData = viewport();

var maxScrollTop = documentHeight - viewPortData.height;

Of course, in your plugin, you should also add a listener on the resize event, and re-calculate the maximum scrollTop.