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

Sougata Ghosh
Sougata Ghosh
6,096 Points
Posted by Sougata Ghosh
Sougata Ghosh
6,096 Points

Paragraph elements color change

Where am i doing wrong?

app.js 
const section = document.querySelector('section');
let paragraphs = section.children;
for (i=0,i<paragraphs.length, i+=1) {
paragraphs.style.backgroundColor = 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>

2 Answers

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,968 Points
KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,968 Points

Some things:

  • Your for loop statements should be separated with semicolons not commas
  • The color blue should be enclosed in quotes
  • As you loop through paragraphs you should be referencing the individual paragraphs by index (ex: paragraphs[i].style.backgroundColor)
Lola Jahn
Lola Jahn
18,718 Points
Lola Jahn
Lola Jahn
18,718 Points

Hey Sougata, You made several mistakes here.

  1. You forgot to declare the variable in the for loop.
  2. You are separating the parts of the for loop with commas instead of semicolons
  3. You never utilised the i in your for loop. 4 You forgot to put double quotes around the string "blue"

The code below works: 

const section = document.querySelector('section');
let paragraphs = section.children;
for (var i=0; i < paragraphs.length; i+=1) {
paragraphs[i].style.backgroundColor = "blue";
}

I suggest you read up on the functionality of the for loop and how to use it. But don't worry, we've all been there.

Sougata Ghosh
Sougata Ghosh
6,096 Points
Sougata Ghosh
Sougata Ghosh
6,096 Points

Thanks much .. i fixed it