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

Adding a class name

I can access the sibling element of the button as the exercise request but I can only remove it with the removeChild method, but I don't understand how to add a class name to a child element.

Any help??

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
        let li = event.target.parentNode;
        let ul = li.parentNode;
        //ul.removeChild(li);
      }
});
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

Steven Parker
Steven Parker
229,005 Points

You still need to access the sibling element. The current code access the parent li and it's parent ul, but you don't need either of those. The previousElementSibling property might be useful here.

And when you get to the sibling, you can overwrite it's classes entirely by assigning the className property, or you can just add to whatever might be there using the classList.add() method.

Awesome, thanks for your help.