Get class list for element with jQuery

Question

Is there a way in jQuery to loop through or assign to an array all of the classes that are assigned to an element?

ex.

        
                      

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Answer 1

I had a similar issue, for an element of type image. I needed to check whether the element was of a certain class. First I tried with:

$('<img>').hasClass("nameOfMyClass"); 

but I got a nice "this function is not available for this element".

Then I inspected my element on the DOM explorer and I saw a very nice attribute that I could use: className. It contained the names of all the classes of my element separated by blank spaces.

$('img').className // it contains "class1 class2 class3"

Once you get this, just split the string as usual.

In my case this worked:

var listOfClassesOfMyElement= $('img').className.split(" ");

I am assuming this would work with other kinds of elements (besides img).

Hope it helps.

Answer 2

The question is what Jquery is designed to do.

$('.dolor_spec').each(function(){ //do stuff

And why has no one given .find() as an answer?

$('div').find('.dolor_spec').each(function(){
  ..
});

There is also classList for non-IE browsers:

if element.classList.contains("dolor_spec") {  //do stuff

Answer 3

javascript provides a classList attribute for a node element in dom. Simply using

  element.classList

will return a object of form

  DOMTokenList {0: "class1", 1: "class2", 2: "class3", length: 3, item: function, contains: function, add: function, remove: function…}

The object has functions like contains, add, remove which you can use

Answer 4

You should try this one:

$("selector").prop("classList")

It returns an array of all current classes of the element.

Answer 5

A bit late, but using the extend() function lets you call "hasClass()" on any element, e.g.:
var hasClass = $('#divId').hasClass('someClass');

(function($) {
$.extend({
    hasClass: new function(className) {
        var classAttr = $J(this).attr('class');
        if (classAttr != null && classAttr != undefined) {
            var classList = classAttr.split(/\s+/);
            for(var ix = 0, len = classList.length;ix < len;ix++) {
                if (className === classList[ix]) {
                    return true;
                }
            }
        }
        return false;
    }
}); })(jQuery);

Answer 6

You can use document.getElementById('divId').className.split(/\s+/); to get you an array of class names.

Then you can iterate and find the one you want.

var classList = document.getElementById('divId').className.split(/\s+/);
for (var i = 0; i < classList.length; i++) {
    if (classList[i] === 'someClass') {
        //do something
    }
}

jQuery does not really help you here...

var classList = $('#divId').attr('class').split(/\s+/);
$.each(classList, function(index, item) {
    if (item === 'someClass') {
        //do something
    }
});