title: scrollheight of an element gives undefined value
body: <p>In an element I've given CSS <code>overflow: scroll;</code>. Now in jQuery I want to have it's original height (containing all child elements' height). Children under this element are dynamically changing. I want to have height on scroll event.
  Here is the code:</p>
  
  <pre><code>$("#container").scroll(function(e) {
      scrollAll();
  });
  
  function scrollAll(){
      var elemHeight = $("#container").scrollHeight;
      var scrollHeight = $("#scrollbars").scrollHeight;
      var ratio = elemHeight / scrollHeight;
  
      $("#outup").html( elemHeight +" and "+ scrollHeight +" ratio "+ ratio +" = "+ ($("#container").scrollTop()));
  }
  </code></pre>
  
  <p>Issue: It throws <code>scrollHeight is undefined</code> error. What's wrong?</p>