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

Posted by William Ray Noble
William Ray Noble
22,190 Points

Help, I've been stuck on this one for a while.

I need to add a class to a previous element but so far everything I've tried hasn't worked. TIA

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let li = event.target.parentNode;
    let prevP = li.previousElementSibling;
    let ul = li.parentNode;
      if (prevP) {
        ul.insertBefore(li, prevP);
      }
  }
});
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>

3 Answers

Zimri Leijen
Zimri Leijen
11,835 Points
Zimri Leijen
Zimri Leijen
11,835 Points

Which part specifically are you stuck on?

William Ray Noble
William Ray Noble
22,190 Points

I wish I knew lol. I'm not sure what I'm getting wrong.

Zimri Leijen
Zimri Leijen
11,835 Points

maybe this helps https://developer.mozilla.org/en-US/docs/Web/API/Element/className

Richard Preske
PLUS
Richard Preske
Courses Plus Student 4,356 Points
Richard Preske
Richard Preske
Courses Plus Student 4,356 Points

I'm stuck too, I took your code and added this: if (event.target.className == "highlight") {

I think you need this condition after the button conditional statement. Getting error saying not a paragraph sibling.