FAQ: Advanced JSX - class vs className

Frequently Asked Questions JavaScript FAQ
1

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This community-built FAQ covers the “class vs className” exercise from the lesson “Advanced JSX”.

Paths and Courses
This exercise can be found in the following Codecademy content:

Web Development

Learn ReactJS: Part I

FAQs on the exercise class vs className

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2

For some reason the instructions say 1. “Lemonade was a popular drink”
2. “Lemonade was a popular drink”

I have to run the code in order to get the real instructions of the lesson… Is that how it’s suppose to be?

Thanks.

Kei

3

no try refreshing the page

4

On step 2 it asks us to write document.getElementById('app')

but why ‘app’? We didn’t give any element an id of ‘app’?

5

I am trying to figure this out as well, super weird. Why is it not ‘big’, the actual className of our div.

import React from 'react';
import ReactDOM from 'react-dom';

// Write code here:
var myDiv = (
  <div className="big">I AM A BIG DIV</div>
);

ReactDOM.render(
  myDiv,
  document.getElementById('app')
)

Can anyone share their knowledge on this?

6

In the top-left corner of the editor, there is a folder icon. If you click on it, you will see a file index.html. Open the file and you will see which element is being targeted by ReactDOM.render

<body>
  <main id="app"></main>
  ...
1 Like