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

Here is a jQuery plugin which will return an array of all the classes the matched element(s) have

;!(function ($) {
    $.fn.classes = function (callback) {
        var classes = [];
        $.each(this, function (i, v) {
            var splitClassName = v.className.split(/\s+/);
            for (var j = 0; j < splitClassName.length; j++) {
                var className = splitClassName[j];
                if (-1 === classes.indexOf(className)) {
                    classes.push(className);
                }
            }
        });
        if ('function' === typeof callback) {
            for (var i in classes) {
                callback(classes[i]);
            }
        }
        return classes;
    };
})(jQuery);

Use it like

$('div').classes();

In your case returns

["Lorem", "ipsum", "dolor_spec", "sit", "amet"]

You can also pass a function to the method to be called on each class

$('div').classes(
    function(c) {
        // do something with each class
    }
);

Here is a jsFiddle I set up to demonstrate and test http://jsfiddle.net/GD8Qn/8/

Minified Javascript

;!function(e){e.fn.classes=function(t){var n=[];e.each(this,function(e,t){var r=t.className.split(/\s+/);for(var i in r){var s=r[i];if(-1===n.indexOf(s)){n.push(s)}}});if("function"===typeof t){for(var r in n){t(n[r])}}return n}}(jQuery);

Answer 2

Thanks for this - I was having a similar issue, as I'm trying to programatically relate objects will hierarchical class names, even though those names might not necessarily be known to my script.

In my script, I want an <a> tag to turn help text on/off by giving the <a> tag [some_class] plus the class of toggle, and then giving it's help text the class of [some_class]_toggle. This code is successfully finding the related elements using jQuery:

$("a.toggle").toggle(function(){toggleHelp($(this), false);}, function(){toggleHelp($(this), true);});

function toggleHelp(obj, mode){
    var classList = obj.attr('class').split(/\s+/);
    $.each( classList, function(index, item){
    if (item.indexOf("_toggle") > 0) {
       var targetClass = "." + item.replace("_toggle", "");
       if(mode===false){$(targetClass).removeClass("off");}
       else{$(targetClass).addClass("off");}
    }
    });
} 

Answer 3

On supporting browsers, you can use DOM elements' classList property.

$(element)[0].classList

It is an array-like object listing all of the classes the element has.

If you need to support old browser versions that don't support the classList property, the linked MDN page also includes a shim for it - although even the shim won't work on Internet Explorer versions below IE 8.

Answer 4

You can follow something like this.

$('#elementID').prop('classList').add('yourClassName')
$('#elementID').prop('classList').remove('yourClassName')

Answer 5

Try This. This will get you the names of all the classes from all the elements of document.

$(document).ready(function() {
var currentHtml="";
$('*').each(function() {
    if ($(this).hasClass('') === false) {
        var class_name = $(this).attr('class');
        if (class_name.match(/\s/g)){
            var newClasses= class_name.split(' ');
            for (var i = 0; i <= newClasses.length - 1; i++) {
                if (currentHtml.indexOf(newClasses[i]) <0) {
                    currentHtml += "."+newClasses[i]+"<br>{<br><br>}<br>"
                }
            }
        }
        else
        {
            if (currentHtml.indexOf(class_name) <0) {
                currentHtml += "."+class_name+"<br>{<br><br>}<br>"
            }
        }
    }
    else
    {
        console.log("none");
    }
});
$("#Test").html(currentHtml);

});

Here is the working example: https://jsfiddle.net/raju_sumit/2xu1ujoy/3/

Answer 6

var classList = $(element).attr('class').split(/\s+/);
$(classList).each(function(index){

     //do something

});