CODEWITHSUNDEEP
javascripthtmlcssclassappend
anonymous
anonymous

Reputation: 2674

JavaScript CSS how to add and remove multiple CSS classes to an element

How can assign multiple css classes to an html element through javascript without using any libraries?

Upvotes: 140

Views: 267026

Answers (20)

Ali Samie
Ali Samie

Reputation: 470

I used String.prototype.split() and Array.prototype.forEach()

"btn btn-sm btn-light my-2".split(" ").forEach(className => locationButton.classList.add(className));

Upvotes: 0

Abhinav Nair
Abhinav Nair

Reputation: 1

By using classname property you can add multiple classes by passing all the classes as a string separated by space. This is more convenient way to do so

newLi.className= "list-group-item d-flex justify-content-between";

Upvotes: 0

Isaac Sichangi
Isaac Sichangi

Reputation: 75

Css classes can be added or removed from DOM elements using the classList property that contains the add or remove functions e.g

Add Css Classes

//you can add multiple classes

 element.classList.add("a", "b", "c");

Remove Css Classes

//you can remove multiple classes

  element.classList.remove("a", "b", "c");

Upvotes: 3

James Ikubi
James Ikubi

Reputation: 2928

2 great ways to ADD:

But the first way is more cleaner, since for the second you have to add a space at the beginning. This is to avoid the class name from joining with the previous class.

element.classList.add("d-flex", "align-items-center");
element.className += " d-flex align-items-center";

Then to REMOVE use the cleaner way, by use of classList

element.classList.remove("d-grid", "bg-danger");

Upvotes: 12

Omar Hegazi
Omar Hegazi

Reputation: 129

the Element.className += " MyClass"; is not recommended approach because it will always add these classes whether they were exit or not.

in my case, I was uploading an image file and adding classes to it, now with this each time you upload an image it will add these class whether they exist or not,

the recommended way is Element.classList.add("class1" , "class2" , "class3"); this way will not add extra classes if they already there.

Upvotes: 2

Balaji
Balaji

Reputation: 10907

ClassList add 

var dynamic=document.getElementById("dynamic");
dynamic.classList.add("red");
dynamic.classList.add("size");
dynamic.classList.add("bold");
.red{
color:red;
}
.size{
font-size:40px;
}
.bold{
font-weight:800;
}
<div id="dynamic">dynamic css</div>

Upvotes: 0

Hossein
Hossein

Reputation: 222

  addClass(element, className1, className2){
    element.classList.add(className1, className2);
  }
  removeClass(element, className1, className2) {
    element.classList.remove(className1, className2);
  }

removeClass(myElement, 'myClass1', 'myClass2');
addClass(myElement, 'myClass1', 'myClass2');

Upvotes: 0

theMaxx
theMaxx

Reputation: 4086

There are at least a few different ways:

var buttonTop = document.getElementById("buttonTop");

buttonTop.className = "myElement myButton myStyle";

buttonTop.className = "myElement";

buttonTop.className += " myButton myStyle";

buttonTop.classList.add("myElement");

buttonTop.classList.add("myButton", "myStyle");

buttonTop.setAttribute("class", "myElement");

buttonTop.setAttribute("class", buttonTop.getAttribute("class") + " myButton myStyle");

buttonTop.classList.remove("myElement", "myButton", "myStyle");

Upvotes: 39

1_bug
1_bug

Reputation: 5717

You can add and remove multiple classes in same way with different in-built methods:

const myElem = document.getElementById('element-id');
//add multiple classes
myElem.classList.add('class-one', 'class-two', 'class-three');
//remove multiple classes
myElem.classList.remove('class-one', 'class-two', 'class-three');

Upvotes: 11

Lemures
Lemures

Reputation: 482

Since I could not find this answer nowhere:

ES6 way (Modern Browsers)

el.classList.add("foo", "bar", "baz");

Upvotes: 9

StackSlave
StackSlave

Reputation: 10627

Maybe this will help you learn:

//<![CDATA[
/* external.js */
var doc, bod, htm, C, E, addClassName, removeClassName; // for use onload elsewhere
addEventListener('load', function(){
doc = document; bod = doc.body; htm = doc.documentElement;
C = function(tag){
  return doc.createElement(tag);
}
E = function(id){
  return doc.getElementById(id);
}
addClassName = function(element, className){
  var rx = new RegExp('^(.+\s)*'+className+'(\s.+)*$');
  if(!element.className.match(rx)){
    element.className += ' '+className;
  }
  return element.className;
}
removeClassName = function(element, className){
  element.className = element.className.replace(new RegExp('\s?'+className), '');
  return element.className;
}
var out = E('output'), mn = doc.getElementsByClassName('main')[0];
out.innerHTML = addClassName(mn, 'wow');
out.innerHTML = addClassName(mn, 'cool');
out.innerHTML = addClassName(mn, 'it works');
out.innerHTML = removeClassName(mn, 'wow');
out.innerHTML = removeClassName(mn, 'main');

}); // close load
//]]>
/* external.css */
html,body{
  padding:0; margin:0;
}
.main{
  width:980px; margin:0 auto;
}
<!DOCTYPE html>
<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en' lang='en'>
  <head>
    <meta http-equiv='content-type' content='text/html;charset=utf-8' />
    <link type='text/css' rel='stylesheet' href='external.css' />
    <script type='text/javascript' src='external.js'></script>
  </head>
<body>
  <div class='main'>
    <div id='output'></div>
  </div>
</body>
</html>

Upvotes: 0

ericsoco
ericsoco

Reputation: 26253

Here's a simpler method to add multiple classes via classList (supported by all modern browsers, as noted in other answers here):

div.classList.add('foo', 'bar'); // add multiple classes

From: https://developer.mozilla.org/en-US/docs/Web/API/Element/classList#Examples

If you have an array of class names to add to an element, you can use the ES6 spread operator to pass them all into classList.add() via this one-liner:

let classesToAdd = [ 'foo', 'bar', 'baz' ];
div.classList.add(...classesToAdd);

Note that not all browsers support ES6 natively yet, so as with any other ES6 answer you'll probably want to use a transpiler like Babel, or just stick with ES5 and use a solution like @LayZee's above.

Upvotes: 176

Lars Gyrup Brink Nielsen
Lars Gyrup Brink Nielsen

Reputation: 4095

In modern browsers, the classList API is supported.

This allows for a (vanilla) JavaScript function like this:

var addClasses;

addClasses = function (selector, classArray) {
    'use strict';

    var className, element, elements, i, j, lengthI, lengthJ;

    elements = document.querySelectorAll(selector);

    // Loop through the elements
    for (i = 0, lengthI = elements.length; i < lengthI; i += 1) {
        element = elements[i];

        // Loop through the array of classes to add one class at a time
        for (j = 0, lengthJ = classArray.length; j < lengthJ; j += 1) {
            className = classArray[j];

            element.classList.add(className);
        }
    }
};

Modern browsers (not IE) support passing multiple arguments to the classList::add function, which would remove the need for the nested loop, simplifying the function a bit:

var addClasses;

addClasses = function (selector, classArray) {
    'use strict';

    var classList, className, element, elements, i, j, lengthI, lengthJ;

    elements = document.querySelectorAll(selector);

    // Loop through the elements
    for (i = 0, lengthI = elements.length; i < lengthI; i += 1) {
        element = elements[i];
        classList = element.classList;

        // Pass the array of classes as multiple arguments to classList::add
        classList.add.apply(classList, classArray);
    }
};

Usage

addClasses('.button', ['large', 'primary']);

Functional version

var addClassesToElement, addClassesToSelection;

addClassesToElement = function (element, classArray) {
    'use strict';

    classArray.forEach(function (className) {
       element.classList.add(className);
    });
};

addClassesToSelection = function (selector, classArray) {
    'use strict';

    // Use Array::forEach on NodeList to iterate over results.
    // Okay, since we’re not trying to modify the NodeList.
    Array.prototype.forEach.call(document.querySelectorAll(selector), function (element) {
        addClassesToElement(element, classArray)
    });
};

// Usage
addClassesToSelection('.button', ['button', 'button--primary', 'button--large'])

The classList::add function will prevent multiple instances of the same CSS class as opposed to some of the previous answers.

Resources on the classList API:

Upvotes: 1

Mano bharathi
Mano bharathi

Reputation: 181

var el = document.getElementsByClassName('myclass')

el[0].classList.add('newclass');

el[0].classList.remove('newclass');

To find whether the class exists or not, use:

el[0].classList.contains('newclass'); // this will return true or false

Browser support IE8+

Upvotes: 15

Maged Rawash
Maged Rawash

Reputation: 43

just use this

element.getAttributeNode("class").value += " antherClass";

take care about Space to avoid mix old class with new class

Upvotes: 3

tybro0103
tybro0103

Reputation: 49713

Try this:

function addClass(element, value) {
  if(!element.className) {
    element.className = value;
  } else {
    newClassName = element.className;
    newClassName+= " ";
    newClassName+= value;
    element.className = newClassName;
  }
}

Similar logic could be used to make a removeClass function.

Upvotes: 1

Tor Valamo
Tor Valamo

Reputation: 33749

guaranteed to work on new browsers. the old className way may not, since it's deprecated.

<element class="oneclass" />

element.setAttribute('class', element.getAttribute('class') + ' another');
alert(element.getAttribute('class')); // oneclass another

Upvotes: 8

Ryan
Ryan

Reputation: 6866

Try doing this...

document.getElementById("MyElement").className += " MyClass";

Got this here...

Upvotes: 92

tarnfeld
tarnfeld

Reputation: 26556

Perhaps:

document.getElementById("myEle").className = "class1 class2";

Not tested, but should work.

Upvotes: 2

moff
moff

Reputation: 6503

This works:

myElement.className = 'foo bar baz';

Upvotes: 48

Related Questions