Source Code: (back to article)
<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style type="text/css">
body {
text-align: center;
}
.oldClassName {
background-color: green;
}
.newClassName {
background-color: blue;
}
.pId {
margin-top: 30px;
}
#buttonId {
padding: 15px;
}
</style>
</head>
<body>
<h2>Chenge class name</h2>
<button class="oldClassName" id="buttonId" onclick="changeClass()">Click on Button</button>
<br>
<p id="pId">Old class name: oldClassName </p>
<script type="text/javascript">
function changeClass() {
document.getElementById('buttonId').className = "newClassName";
let button_class = document.getElementById('buttonId').className;
document.getElementById('pId').innerHTML = "New class name: " + button_class;
}
</script>
</body>
</html>