ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
120 lines
3.0 KiB
Markdown
120 lines
3.0 KiB
Markdown
---
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id: 5a24c314108439a4d4036172
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title: Render State in the User Interface Another Way
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challengeType: 6
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forumTopicId: 301408
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dashedName: render-state-in-the-user-interface-another-way
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---
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# --description--
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There is another way to access `state` in a component. In the `render()` method, before the `return` statement, you can write JavaScript directly. For example, you could declare functions, access data from `state` or `props`, perform computations on this data, and so on. Then, you can assign any data to variables, which you have access to in the `return` statement.
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# --instructions--
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In the `MyComponent` render method, define a `const` called `name` and set it equal to the name value in the component's `state`. Because you can write JavaScript directly in this part of the code, you don't have to enclose this reference in curly braces.
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Next, in the return statement, render this value in an `h1` tag using the variable `name`. Remember, you need to use the JSX syntax (curly braces for JavaScript) in the return statement.
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# --hints--
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`MyComponent` should have a key `name` with value `freeCodeCamp` stored in its state.
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```js
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assert(
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Enzyme.mount(React.createElement(MyComponent)).state('name') ===
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'freeCodeCamp'
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);
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```
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`MyComponent` should render an `h1` header enclosed in a single `div`.
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```js
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assert(
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/<div><h1>.*<\/h1><\/div>/.test(
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Enzyme.mount(React.createElement(MyComponent)).html()
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)
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);
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```
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The rendered `h1` tag should include a reference to `{name}`.
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```js
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(getUserInput) =>
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assert(/<h1>\n*\s*\{\s*name\s*\}\s*\n*<\/h1>/.test(getUserInput('index')));
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```
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The rendered `h1` header should contain text rendered from the component's state.
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```js
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async () => {
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const waitForIt = (fn) =>
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new Promise((resolve, reject) => setTimeout(() => resolve(fn()), 250));
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const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
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const first = () => {
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mockedComponent.setState({ name: 'TestName' });
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return waitForIt(() => mockedComponent.html());
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};
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const firstValue = await first();
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assert(firstValue === '<div><h1>TestName</h1></div>');
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};
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```
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# --seed--
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## --after-user-code--
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```jsx
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ReactDOM.render(<MyComponent />, document.getElementById('root'))
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```
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## --seed-contents--
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```jsx
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class MyComponent extends React.Component {
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constructor(props) {
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super(props);
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this.state = {
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name: 'freeCodeCamp'
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}
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}
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render() {
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// Change code below this line
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// Change code above this line
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return (
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<div>
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{ /* Change code below this line */ }
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{ /* Change code above this line */ }
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</div>
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);
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}
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};
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```
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# --solutions--
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```jsx
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class MyComponent extends React.Component {
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constructor(props) {
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super(props);
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this.state = {
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name: 'freeCodeCamp'
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}
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}
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render() {
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// Change code below this line
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const name = this.state.name;
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// Change code above this line
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return (
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<div>
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{ /* Change code below this line */ }
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<h1>{name}</h1>
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{ /* Change code above this line */ }
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</div>
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);
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}
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};
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```
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