jQuery Check if Element has Class Attached

jQuery code snippet to check whether a web page element has a specific css class attached. Could be used to check if the element needs additional formatting or if you want to protect certain page elements. To do this we can use the jQuery hasClass() function or jQuery is() function.

<span>$("div").click(function(){
</span>	<span>if ( $(this).hasClass("protected") ) {
</span>		<span>//do something it does have the protected class!
</span>		<span>alert("i have the protected class");
</span>	<span>}
</span><span>});</span>

OR

<span>$("div").click(function(){
</span>   <span>if ( $('#myDiv').is('.pretty.awesome') ) {
</span>	   <span>//do something it does have the protected class!
</span>	   <span>alert("i have the pretty and awesome classes");
</span>   <span>}
</span><span>});</span>

Note: that this method allows you to test for other things as well. IE – Check if an element is hidden.

<span>if ( $('#myDiv').is(':hidden') ) {
</span>   <span>//do something I am hidden!
</span>   <span>alert("i am hidden!");
</span><span>}</span>

Frequently Asked Questions (FAQs) about jQuery and Element Classes

How can I use jQuery to check if an element has multiple classes?

In jQuery, you can check if an element has multiple classes by using the hasClass() method in combination with logical operators. For instance, if you want to check if an element has both ‘class1’ and ‘class2’, you can use the following code:

if ($('#element').hasClass('class1') && $('#element').hasClass('class2')) {
// Do something
}
In this code, $('#element') selects the element with the id ‘element’, and hasClass('class1') and hasClass('class2') check if the element has ‘class1’ and ‘class2’ respectively. The && operator ensures that both conditions must be true.

Can I use jQuery to add a class to an element if it doesn’t already have it?

Yes, you can use the addClass() method in jQuery to add a class to an element if it doesn’t already have it. Here’s how you can do it:

if (!$('#element').hasClass('class1')) {
$('#element').addClass('class1');
}
In this code, $('#element') selects the element with the id ‘element’, and hasClass('class1') checks if the element has ‘class1’. If it doesn’t, addClass('class1') adds ‘class1’ to the element.

How can I remove a class from an element using jQuery?

You can use the removeClass() method in jQuery to remove a class from an element. Here’s an example:

$('#element').removeClass('class1');
In this code, $('#element') selects the element with the id ‘element’, and removeClass('class1') removes ‘class1’ from the element.

Can I check if an element has any class at all using jQuery?

Yes, you can check if an element has any class at all using jQuery. You can do this by checking if the attr('class') method returns undefined. Here’s how you can do it:

if ($('#element').attr('class') !== undefined) {
// Do something
}
In this code, $('#element') selects the element with the id ‘element’, and attr('class') gets the class attribute of the element. If it’s not undefined, the element has at least one class.

How can I toggle a class on an element using jQuery?

You can use the toggleClass() method in jQuery to toggle a class on an element. This means that if the element has the class, it will be removed; if it doesn’t have the class, it will be added. Here’s an example:

$('#element').toggleClass('class1');
In this code, $('#element') selects the element with the id ‘element’, and toggleClass('class1') toggles ‘class1’ on the element.

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