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

Edmundo Ruiz
Edmundo Ruiz
3,488 Points
Posted by Edmundo Ruiz
Edmundo Ruiz
3,488 Points

Been stuck for a while

I cant seem to create the right selection.

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
            if(e.target.tagName == 'P'){

      }    
  }
});
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

Adam Pengh
Adam Pengh
29,881 Points
Adam Pengh
Adam Pengh
29,881 Points

You want to select the <p> element immediately before the <button> element. The <p> element would be a sibling and is previous to the <button> element, so you would select it using the .previousElementSibling method like so:

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

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