I'm trying to set `onClick` on `href` which able to select all the checkbox, however my code are able to select all the checkbox but how do I deselect the checkbox if I `onClick` the button again? Kindly advise.

HTML
----

```
<input type="checkbox" name="fool1" id="fool1"> 
<input type="checkbox" name="fool2" id="fool2">

 <a href="#" class="action_link padding-10" id="selectAll" value="selectAll">全选</a> 

```

jQuery
------

```
$(document).ready(function() {
    $('#selectAll').click(function() {
        $("input:checkbox").attr('checked', true);
    });
});

```