freeCodeCamp/curriculum/challenges/english/03-front-end-libraries/react/write-a-react-component-fro...

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---
id: 5a24c314108439a4d4036168
title: Write a React Component from Scratch
challengeType: 6
forumTopicId: 301424
dashedName: write-a-react-component-from-scratch
---
# --description--
Now that you've learned the basics of JSX and React components, it's time to write a component on your own. React components are the core building blocks of React applications so it's important to become very familiar with writing them. Remember, a typical React component is an ES6 `class` which extends `React.Component`. It has a render method that returns HTML (from JSX) or `null`. This is the basic form of a React component. Once you understand this well, you will be prepared to start building more complex React projects.
# --instructions--
Define a class `MyComponent` that extends `React.Component`. Its render method should return a `div` that contains an `h1` tag with the text: `My First React Component!` in it. Use this text exactly, the case and punctuation matter. Make sure to call the constructor for your component, too.
Render this component to the DOM using `ReactDOM.render()`. There is a `div` with `id='challenge-node'` available for you to use.
# --hints--
There should be a React component called `MyComponent`.
```js
(getUserInput) =>
assert(
__helpers
.removeWhiteSpace(getUserInput('index'))
.includes('classMyComponentextendsReact.Component{')
);
```
`MyComponent` should contain an `h1` tag with text `My First React Component!` Case and punctuation matter.
```js
assert(
(function () {
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
return mockedComponent.find('h1').text() === 'My First React Component!';
})()
);
```
`MyComponent` should render to the DOM.
```js
assert(document.getElementById('challenge-node').childNodes.length === 1);
```
`MyComponent` should have a constructor calling `super` with `props`.
```js
assert(
MyComponent.toString().includes('MyComponent(props)') &&
MyComponent.toString().includes('_super.call(this, props)')
);
```
# --seed--
## --seed-contents--
```jsx
// Change code below this line
```
# --solutions--
2020-07-13 16:58:50 +00:00
```jsx
// Change code below this line
class MyComponent extends React.Component {
constructor(props) {
super(props);
}
render() {
return (
<div>
<h1>My First React Component!</h1>
</div>
);
}
};
ReactDOM.render(<MyComponent />, document.getElementById('challenge-node'));
```