Pick up the second class

The quickest thing that occurred to me is to use split() :

$('input[name="Form1a1"]').attr('class').split(' ')[1];

Example:

$(function() {
  alert($('input[name="Form1a1"]').attr('class').split(' ')[1]);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script><inputtype="radio" value="5" name="Form1a1" class="abobrinha Form1comentarioA" />

In the example we are:

Catch the last class

If the idea is to get the last class, instead of getting the input 1 of the resulting array, we can jump to the end of it using the .pop() :

$('input[name="Form1a1"]').attr('class').split(' ').pop();

Example:

$(function() {
  alert($('input[name="Form1a1"]').attr('class').split(' ').pop());
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script><inputtype="radio" value="5" name="Form1a1" class="abobrinha algumaCoisaMais Form1comentarioA" />

$(":radio[name='Form1a1']").attr('class').split(' ')[1]

Explanation:

• $(":radio[name='Form1a1']") - gets the list of all Radiobuttons that have the attribute name equal to Form1a1 ;
• .attr('class') - gets the value of the 'class' attribute;
• .split(' ') - transforms the string into an array of strings, using whitespace as a divider;
• [1] - gets the second member of the collection.

Source:

Original SO, ' How to get the second class name from element? '

The other answers refer well to doing this with jQuery. Actually you do not need jQuery for this. It can be done with native JavaScript like this:

var segundaClasse = document.querySelector('input[type="radio"]').classList[1];

The .classList is an array with all element classes . Selecting position 1 gives the second class (because the arrays start indexing at zero).

example: link