jquery a addclass code example
Example 1: add class jquery
$("#my_id").attr("class", "my_new_class_name");
Example 2: 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>