Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Albert Egberg
Albert Egberg
7,786 Points
Posted by Albert Egberg
Albert Egberg
7,786 Points

[SOLVED] Change color to blue for each paragraph.

I don't understand why it won't work?

app.js 
var section = document.querySelectorAll('section');
var paragraphs = section.children;

for (let i = 0; i < paragraphs.length; i += 1) {
  paragraphs[i].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; 2019</p> 
        </footer>
        <script src="app.js"></script>
    </body>
</html>
Albert Egberg
Albert Egberg
7,786 Points
Albert Egberg
Albert Egberg
7,786 Points

If I'd change the fitst line of code to: const section = document.querySelectorAll('section'); it'd work.

3 Answers

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,967 Points

I tried this in a workspace and found in using querySelectorAll that an index had to be used to access the children even though there was only one section. The following will change the paragraph colors:

var section = document.querySelectorAll("section")[0];
var paragraphs = section.children;

for (let i = 0; i < paragraphs.length; i += 1) {
  paragraphs[i].style.color = 'blue';
}

and was accepted by the challenge.

Albert Egberg
Albert Egberg
7,786 Points
Albert Egberg
Albert Egberg
7,786 Points

I eventually solved it, but this works aswell! Thanks for the help :)

<noob />
<noob />
17,062 Points
<noob />
<noob />
17,062 Points 
var section = document.querySelector('section');

var paragraphs = section.children;

for(var i = 0; i < paragraphs.length; i++) {
  paragraphs[i].style.color = "blue";
}

try to use var instead of let in the loop

<noob />
<noob />
17,062 Points
<noob />
<noob />
17,062 Points

KRIS NIKOLAISEN

take a look, i will be happy if u can help there :] https://teamtreehouse.com/community/trying-to-filter-options-with-pure-js

Albert Egberg
Albert Egberg
7,786 Points
Albert Egberg
Albert Egberg
7,786 Points

You are too smart for me, I don't understand PHP ;)