How can I get the browser's scrollbar sizes?

Question

How can I determine the height of a horizontal scrollbar, or the width of a vertical one, in JavaScript?

Answer 1

The way Antiscroll.js does it in it's code is:

function scrollbarSize () {
  var div = $(
      '
'
    + '
'
  );

  $('body').append(div);
  var w1 = $(div).innerWidth();
  var w2 = $('div', div).innerWidth();
  $(div).remove();

  return w1 - w2;
};

The code is from here: https://github.com/LearnBoost/antiscroll/blob/master/antiscroll.js#L447