add class to a div jquery code example

Example 1: jquery add class

$('some_element').addClass('some-class');

// You can add more than one class at one time
$('some_element').addClass('some-class another-class yet-another-class');

// Even thought jQuery allows you to do this
$('some_element').addClass('some-class').addClass('another-class').addClass('yet-another-class');

// That would be really wasteful, think of the planet!
// But more importantly, your RAM
// oh and those poor folks who be viewing your website

Example 2: jquery addclass

$("#elem").addClass("classname");

Example 3: jquery addclass

$( "p" ).addClass( "myClass yourClass" );

Example 4: add class jquery

$("#my_id").attr("class", "my_new_class_name");

Example 5: jquery add multiple classes

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>addClass demo</title>
  <style>
  p {
    margin: 8px;
    font-size: 16px;
  }
  .selected {
    color: red;
  }
  .highlight {
    background: yellow;
  }
  </style>
  <script src="https://code.jquery.com/jquery-3.4.1.js"></script>
</head>
<body>
 
<p>Hello</p>
<p>and</p>
<p>Goodbye</p>
 
<script>
$( "p" ).last().addClass( "selected highlight" );
</script>
 
</body>
</html>

Example 6: how to add class on the base of has class in jquery

$( "ul li" ).addClass(function( index ) {
  return "item-" + index;
});