HTML DOM setNamedItem() Method

The setNamedItem() method is used to add a particular node to an attribute node using its name. These attribute nodes are collectively called as namedNodeMap. It can be accessed through a name. If a node is already present in the document, it will replace it and return the updated value. The setNamedItem() method requires a node as a parameter.

Syntax:

namedNodeMap.setNamedItem( node )

Parameter Value: This method contains a single parameter node which is mandatory. This parameter is the node value that need to add or replace in the namedNodeMap collection.

Return Value: It returns a Node object that, represents the replaced node (if any), otherwise null

Example 1: In this example, we will use the setNamedItem() method.

HTML

<!DOCTYPE html>
<html>
<head>
    <title>
        DOM setNamedItem() Method
    </title>
    <style>
        .gfg {
            color: green;
            font-size: 40px;
        }
    </style>
</head>
<body>
    <h1 class="geeks1">GeeksforGeeks</h1>
    <h2 class="geeks2">DOM setNamedItem() Method</h2>
    <button onclick="setNameItem()">
        Set Node
    </button>
    <script>
        function setNameItem() {
            // It is used to fetch the text
            // present in class geeks1
            let one =
                document.getElementsByClassName("geeks1")[0];
            // New class (geek) is created
            let geek = document.createAttribute("class");
 
            // Passing value of gfg class into geek class
            geek.value = "gfg";
            // Updating the CSS property of geeks1
            // class to gfg class
            one.attributes.setNamedItem(geek);
        }
    </script>
</body>
</html>

Output:

Example 2: In this example, we will use the setNamedItem() method.

HTML

<!DOCTYPE html>
<html>
<head>
    <title>
        DOM setNamedItem() Method
    </title>
    <!-- Set CSS property to the element -->
    <style>
        .gfg {
            color: green;
            font-size: 40px;
        }
        .gfg1 {
            color: green;
            font-size: 40px;
        }
    </style>
</head>
 
<body style="text-align:center">
 
    <h1>GeeksforGeeks</h1>
    <h2>DOM setNamedItem() Method</h2>
    <h3>Welcome to GeeksforGeeks</h3>
    <button onclick="setNameItem()">
        Set Node
    </button>
    <script>
        function setNameItem() {
            let one =
                document.getElementsByTagName("H1")[0];
            let geek =
                document.createAttribute("class");
            geek.value = "gfg";
            one.attributes.setNamedItem(geek);
 
            let two =
                document.getElementsByTagName("H3")[0];
            let geek1 =
                document.createAttribute("class");
            geek1.value = "gfg1";
            two.attributes.setNamedItem(geek1);
        }
    </script>
</body>
 
</html>