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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Sibling Traversal

Sibling Transversal

Hello,

I need to create the Class name ‘highlight’ in the previous Element Sibling of the <p> Element once the button has been clicked.

app.js
var list = document.getElementsByTagName('ul')[0];
var paragraph = document.querySelector('p').previousElementSibling;

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
  paragraph.className = 'highlight'
  }
});
index.html
<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section>
            <h1>Making a Webpage Interactive</h1>
            <p>Things to Learn</p>
            <ul>
                <li><p>Element Selection</p><button>Highlight</button></li>
                <li><p>Events</p><button>Highlight</button></li>
                <li><p>Event Listening</p><button>Highlight</button></li>
                <li><p>DOM Traversal</p><button>Highlight</button></li>
            </ul>
        </section>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

Steven Parker
Steven Parker
231,008 Points

You can't identify the correct paragraph until the button is clicked. Then you can use traversal attributes of the button itself to find it.