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

Posted by Caroline Louw
Caroline Louw
12,155 Points

how do i add the class highlight to the p element?

do i use previousElementSibling or previousSibling?

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

list.addEventListener('click', function(e) {
if (e.target.tagName == 'BUTTON') {
  let p = e.target.previousSibling;
  p.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

Rabin Gharti Magar
.a{fill-rule:evenodd;}techdegree seal-36
Rabin Gharti Magar
Front End Web Development Techdegree Graduate 20,928 Points

Hey Caroline Louw,

You can use previousElementSibling like this:

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    const target = e.target;
    target.previousElementSibling.className = "highlight";
  }
});

Hope this helps!