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

Ian Olson
Ian Olson
2,204 Points
Posted by Ian Olson
Ian Olson
2,204 Points

Choosing wrong Elements or not calling the right sibling?

Looks like I'm not calling the right sibling but not sure if i need to use the highlight class or go outside the paragraph node.

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

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

bjork
bjork
2,400 Points
bjork
bjork
2,400 Points

Hi Ian

I think you have the end parenthesis in the wrong place, resulting in a try to call previousElementSibling on the string “highlight” and string has no such method. Just move that little parenthesis so you get

let list = document.getElementsByClassName('highlight').previousElementSibling;

Good luck, may the highlighting force be with you.

Dylan Sieren
Dylan Sieren
2,339 Points
Dylan Sieren
Dylan Sieren
2,339 Points

I agree with bjork, There is an error with how you're trying to get that sibling element. it will go document.element(class).something.