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

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

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

3 Answers

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

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

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

Albert Egberg
Albert Egberg
7,786 Points

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