之后/之前的jQuery addClass

Question

<div id="box"></div>
<div class="text"></div>?



$(document).ready(function () { 
$('#box').click(function () {
      $('.text').slideToggle('slow');
  });


});


#box{
height:40px;
width:100px;
background:red;
}

#box:hover{background:blue;}

#box:after{
content: "";
height: 10px;
position: absolute;
width: 0;
margin-top:40px;
margin-left:40px;
border: 10px solid transparent;
border-top-color: red;
}


#box:hover:after{

border-top-color: blue;
}

.text{

display:none;
height:40px;
width:100px;
background:#fd0;
margin-top:20px;
}

http://jsfiddle.net/zfQvD/16/

Is that possible to use jQuery to add the styled after arrow? when text class is closed, remove after arrow class if text class is shown, then add the arrow? I tried, but seems doesn't work

Answer 1

As per @elclanrs comment, you can't add pseudo elements with JS. What you can do, however, is declare them in your CSS to be only shown when a parent element has a specific class, and then toggle this class with JS, like this:

#box.expanded:after {
 content:'';
 height: 10px;
 position: absolute;
 width: 0;
 margin-top:40px;
 margin-left:40px;
 border: 10px solid transparent;
 border-top-color: red;
}

You also have to add a line to your JS for this class to be added upon clicking the box:

$('#box').click(function () {
  $(this).toggleClass('expanded');
  $('.text').slideToggle('slow');
});

See the example here: http://jsfiddle.net/zfQvD/17/