change classname js code example

Example 1: js add class

var element = document.getElementById('element');
element.classList.add('class-1');
element.classList.add('class-2', 'class-3');
element.classList.remove('class-3');

Example 2: change class javascript

Syntax:
document.getElementById('myElement').className = "myclass";

<html> 
    <head> 
        <title>Change class of an element with javascript</title> 
        <style type="text/css"> 
            .redbutton{ 
                background-color: red; 
            } 
            .greenbutton{ 
                background-color: green; 
            } 
        </style> 
        <script type="text/javascript"> 
            function changeClass() { 
                document.getElementById('clickme').className = "greenbutton"; 
                var new_class = document.getElementById('clickme').className; 
                document.getElementById('classChange').innerHTML = "New Class Name : "  
                + new_class; 
            } 
        </script> 
    </head> 
    <body> 
        <button class="redbutton" id="clickme" onclick="changeClass()" 
                    >Change Class</button><br> 
        <p id="classChange">Class Name: redbutton</p> 
    </body> 
</html>

Example 3: classnames javascri+t

Installation:
yarn add classnames or npm i classnames

Usage:
classNames('foo', 'bar'); // => 'foo bar'
classNames('foo', { bar: true }); // => 'foo bar'
classNames({ 'foo-bar': true }); // => 'foo-bar'
classNames({ 'foo-bar': false }); // => ''
classNames({ foo: true }, { bar: true }); // => 'foo bar'
classNames({ foo: true, bar: true }); // => 'foo bar'
 
// lots of arguments of various types
classNames('foo', { bar: true, duck: false }, 'baz', { quux: true }); // => 'foo bar baz quux'
 
// other falsy values are just ignored
classNames(null, false, 'bar', undefined, 0, 1, { baz: null }, ''); // => 'bar 1'

TypeInstallation:
yarn add @types/classnames

Tags:

Java Example

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