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

Jiho Song
Jiho Song
16,469 Points
Posted by Jiho Song
Jiho Song
16,469 Points

what's wrong with my code?

everything seems perfectly fine and even added new code to see if it works.

and it works! why it fail??

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    e.target.previousElementSibling.className = "hightlight";
    for(let i=0; i<document.querySelectorAll(".hightlight").length; i++){

    document.querySelectorAll(".hightlight")[i].style.background = "red";
    }
  }
});
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

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

You have a spelling error.

On line 5, you spelled "hightlight" (with an extra "t") instead of "highlight".

But then it looks like you also added some extra lines that are not needed.