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

Adding a class of highlight to a <p> element not working

Can you see where I am wrong? Thanks.

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

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

2 Answers

Hey Mohamed Boussaid,

In your code, you don't have to create any new variables. You can target <p> element by using previousElementSibling when the button is clicked like this:

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

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

Hope this helps!

Awesome!