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

Jase Hackman
Jase Hackman
4,320 Points
Posted by Jase Hackman
Jase Hackman
4,320 Points

I keep getting (evaluating 'newColor.style') error

I can't figure out why I am getting this error. As far as I can tell the code is running as it should. It is turning the paragraphs blue.

app.js 
const section = document.querySelector('section');
let paragraphs = section.children;

for (var i = 0; i <= paragraphs.length; i++) {
  var newColor = paragraphs[i];
  newColor.style.color = "blue";
}
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>Child Traversal</title>
    </head>
    <body>
        <section>
            <p>This is the first paragraph</p>
            <p>This is a slightly longer, second paragraph</p>
            <p>Shorter, last paragraph</p>
        </section>
        <footer>
            <p>&copy; 2016</p> 
        </footer>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

If you check the console you'll see Uncaught TypeError: Cannot read property 'style' of undefined. This comes from the upper bound of your for loop.

Instead of: 

i <= paragraphs.length

it should be

i < paragraphs.length
Jase Hackman
Jase Hackman
4,320 Points
Jase Hackman
Jase Hackman
4,320 Points

That fixed it! Thanks!