How to clear all checkbox When checkbox `id="checkAll"` are checked ?

in my demo , when user checked checkbox `id="checkAll"` all checkbox are checked

But i want to apply to , when user checked checkbox `id="checkAll"` all checkbox are clear , How can i do ?

<http://jsfiddle.net/peap/sydzL8Lc/1/>

```
$('#checkAll').click(function () {    
     $('input:checkbox').prop('checked', this.checked);       
 });

```