Web-Development/06_using.html at main · arnab812/Web-Development · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body id="body">
    <!-- How to access attributes : -->
    <!-- IDs & Classes are object elements (primitive in HTML)-->
    <ul id="element" data="valid"> <!-- self made attribute - 'data'-->
        <li>First element</li>
        <li>Second element</li>
        <li>Third element</li>
    </ul>

    <div id="vanish">
        <h2>NULL</h2>
        <h2>to be vanished</h2>
    </div>

    <script>
        // trying to access the attribute 'data'  -
        console.log(element.id); // output : element
        console.log(element.data); // output : undefined

        // predefined HTML attributes are treated as object properties

        // ***** the way to access user-defined attributes :
        console.log(element.getAttribute('data'));

        // set attribute, getAttribute, hasAttribute :
        console.log(element.setAttribute('order-placed', 'pending'));
        console.log(element.getAttribute('order-placed'));
        console.log(element.hasAttribute('order-placed')); // checks whether an attribute is present or not in the element, outputs in boolean form
        console.log(element.removeAttribute('order-placed'));
        console.log(element.getAttribute('order-placed'));

        // to check all the attributes in an element :
        console.log(element.attributes);

        // -------------------------------------------------------------------------------------------------------------- //

        // * Creating, updating and removing elements :
        // elements that get created inside script tag, do not get added into DOM, can get returned in a form of a variable -

        const newDiv = document.createElement('div');
        /*
        // add the newly created element 'div' into DOM - append() : append adds an element at the end
        // adding a node to the newly crated 'div' tag :
        const newText = document.createTextNode("JavaScript features 'Hoisting'"); // node creation
        newDiv.appendChild(newText); // 'newDiv' appends 'newText'
        body.append(newDiv); // 'body' (id of the 'body' tag) appends the 'newDiv' tag

        // prepend() : adds an element at the top
        body.prepend(newDiv);

        // before() & after() :
        body.after(newDiv); // adds a tag after the 'body' tag
        body.before(newDiv); // adds a tag before the 'body' tag

        // replaceWith() :
        // vanish.replaceWith(newDiv);

        // remove()
        vanish.remove();
        */
        newDiv.innerHTML = `<ul id="element" data="valid">
        <li>First element</li>
        <li>Second element</li>
        <li>Third element</li>
        </ul>`


    </script>
</body>
</html>