<h1class="ui-widget-header"><ahref="http://dev.jqueryui.com/ticket/4071">#4071 - 'length' is null or not an object</a></h1>
<h2>Summary</h2>
In Internet Explorer, when a event such as click on one element causes a change event on another element to trigger programmatically, any change event handler that was bound to that second element through onchange gets the click event instead of the change event.
<h2>Steps to reproduce</h2>
<p>
To demonstrate the issue, do one of the following:
</p>
<ul>
<li>Click the input to open the Datepicker, then select a date</li>
<li>Or press a number in the text field and blur</li>
<li>Or click a button below</li>
</ul>
<p>
Each will trigger change on the text input. The input has a handler bound in three different ways. Notice the difference when pressing a number in the input and bluring versus either selecting a date or pressing one of the first three buttons. In Internet Explorer, when the issue is present, 2 out of the three event objects are of type 'click' instead of 'change' and have the wrong corresponding srcElement/target when the datepicker or one of the first three buttons are clicked.