Get class name using jQuery

Multiple classes? No problem!

When an element has multiple classes associated, using .attr('class').split(' ') you can effortlessly transform the space-separated string of classes into an array:

var allClassesArray = $('#elementId').attr('class').split(' '); // The more, the merrier
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This array of class names enables for easy parsing or manipulation as required.

Check before you wreck

Before manipulating any of the classes, ensure the class exists on the element. Use the .hasClass() function to verify class existence:

if ($('#elementId').hasClass('targetClass')) {
    // Element has 'targetClass'... fingers crossed.
}
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This check is efficient, needing no parsing of the complete class list.

Event handling and class access

Within jQuery event handlers, get class names using good ol' JavaScript:

$('#elementId').click(function() {
    var classNames = this.className; // No jQuery? No problem! 
    var id = this.id; // ID, you're next!
});
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Here the this refers to the pertinent DOM element, giving you access to properties like className and id.

Advanced target selection

For complex scenarios like selecting a specific div within an identified element, you can blend jQuery selectors and filters:

var fifteenthDivClass = $('#sidebar div:eq(14)').attr('class'); // Fifteen... the sweet spot!
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This retrieve the class from the 15th div, adapting to jQuery's zero-indexed element selections.

Using modern JavaScript for class and ID access

Fond of modern JavaScript and dislike jQuery? Use this for achieving the same results:

const element = document.querySelector('#elementId');
const classNames = element.className; // Classy move!
const id = element.id; // ID-eally speaking
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Listing all classes:

const classListArray = Array.from(element.classList); // We got 'em all!
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These native DOM properties have substantial browser support and serve as a jQuery-free shortcut for simple DOM manipulations.

Fetching live (dynamic) class data

When classes dynamically update, ensure you get the most recent class data. Always fetch class names within the event handler or method for latest statuses:

$('#elementId').click(function() {
    var classNames = this.className; // Always up-to-date! 
});
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Crafting jQuery selectors from classes

Transform an element's classes into a jQuery selector:

const selector = '.' + $('#myDiv').attr('class').split(' ').join('.'); // A fine transformation indeed!
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The code above connects all classes with dots, simplifying targeting of elements sharing the same classes.

Working with .attr() function beyond classes

The .attr() function is a truly versatile tool, fetching any attribute:

var typeAttr = $('#myInput').attr('type'); // Spying on my attributes now, are we?
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The power of .attr() is not confined to handling classes, but is an indispensable tool for dealing with attributes across jQuery.