Question

Having table

 <table>
  <tr><td></td><td class="foo"></td></tr>
  <tr><td></td><td class="bar"></td></tr>
 </table>

How to get all td elements having any class set?

While trying

$.each($("td:not(undefined)"),function(i,v){ ...

i still get undefined class in result

Answer 1

Try

$("td[class]").each(function(i,v){ ...

The attribute selector selects elements with the given attribute see the docs.

As pimvdb pointed out [class!=''] will filter out elements which have no classes but has the class attribute (i.e. an empty class attribute). Also, you can use .each directly on a jQuery set.

Also see the selectors specification.