* chore: rename APIs and Microservices to include "Backend" (#42515) * fix typo * fix typo * undo change * Corrected grammar mistake Corrected a grammar mistake by removing a comma. * change APIs and Microservices cert title * update title * Change APIs and Microservices certi title * Update translations.json * update title * feat(curriculum): rename apis and microservices cert * rename folder structure * rename certificate * rename learn Markdown * apis-and-microservices -> back-end-development-and-apis * update backend meta * update i18n langs and cypress test Co-authored-by: Shaun Hamilton <shauhami020@gmail.com> * fix: add development to front-end libraries (#42512) * fix: added-the-word-Development-to-front-end-libraries * fix/added-the-word-Development-to-front-end-libraries * fix/added-word-development-to-front-end-libraries-in-other-related-files * fix/added-the-word-Development-to-front-end-and-all-related-files * fix/removed-typos-from-last-commit-in-index.md * fix/reverted-changes-that-i-made-to-dependecies * fix/removed xvfg * fix/reverted changes that i made to package.json * remove unwanted changes * front-end-development-libraries changes * rename backend certSlug and README * update i18n folder names and keys * test: add legacy path redirect tests This uses serve.json from the client-config repo, since we currently use that in production * fix: create public dir before moving serve.json * fix: add missing script * refactor: collect redirect tests * test: convert to cy.location for stricter tests * rename certificate folder to 00-certificates * change crowdin config to recognise new certificates location * allow translations to be used Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com> * add forwards slashes to path redirects * fix cypress path tests again * plese cypress * fix: test different challenge Okay so I literally have no idea why this one particular challenge fails in Cypress Firefox ONLY. Tom and I paired and spun a full build instance and confirmed in Firefox the page loads and redirects as expected. Changing to another bootstrap challenge passes Cypress firefox locally. Absolutely boggled by this. AAAAAAAAAAAAAAA * fix: separate the test Okay apparently the test does not work unless we separate it into a different `it` statement. >:( >:( >:( >:( Co-authored-by: Sujal Gupta <55016909+heysujal@users.noreply.github.com> Co-authored-by: Noor Fakhry <65724923+NoorFakhry@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com>
88 lines
2.6 KiB
Markdown
88 lines
2.6 KiB
Markdown
---
|
|
id: 5a24c314108439a4d403617c
|
|
title: Usare il metodo del ciclo di vita componentWillMount
|
|
challengeType: 6
|
|
forumTopicId: 301423
|
|
dashedName: use-the-lifecycle-method-componentwillmount
|
|
---
|
|
|
|
# --description--
|
|
|
|
I componenti React hanno diversi metodi speciali che offrono l'opportunità di eseguire azioni in punti specifici del ciclo di vita di un componente. Questi sono chiamati metodi del ciclo di vita, o hooks (ganci) del ciclo di vita, e consentono di intercettare i componenti in determinati istanti. Ad esempio prima che sia fatto il render del componente, prima di aggiornarlo, prima di ricevere le prop, prima di smontarlo, e così via. Ecco un elenco di alcuni dei principali metodi del ciclo di vita: `componentWillMount()` `componentDidMount()` `shouldComponentUpdate()` `componentDidUpdate()` `componentWillUnmount()` Le prossime lezioni copriranno alcuni dei casi di base per questi metodi del ciclo di vita.
|
|
|
|
**Nota:** Il metodo del ciclo di vita `componentWillMount` sarà deprecato in una versione futura di 16.X e rimosso nella versione 17. [(Fonte)](https://reactjs.org/blog/2018/03/27/update-on-async-rendering.html)
|
|
|
|
# --instructions--
|
|
|
|
Il metodo `componentWillMount()` viene chiamato prima del metodo `render()` quando un componente viene montato sul DOM. Scrivi qualcosa nella console all'interno di `componentWillMount()` - potresti aprire la console del browser per vedere l'output.
|
|
|
|
# --hints--
|
|
|
|
`MyComponent` dovrebbe presentare un elemento `div`.
|
|
|
|
```js
|
|
assert(
|
|
(function () {
|
|
const mockedComponent = Enzyme.mount(React.createElement(MyComponent));
|
|
return mockedComponent.find('div').length === 1;
|
|
})()
|
|
);
|
|
```
|
|
|
|
`console.log` dovrebbe essere chiamato in `componentWillMount`.
|
|
|
|
```js
|
|
assert(
|
|
(function () {
|
|
const lifecycle = React.createElement(MyComponent)
|
|
.type.prototype.componentWillMount.toString()
|
|
.replace(/ /g, '');
|
|
return lifecycle.includes('console.log(');
|
|
})()
|
|
);
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --after-user-code--
|
|
|
|
```jsx
|
|
ReactDOM.render(<MyComponent />, document.getElementById('root'))
|
|
```
|
|
|
|
## --seed-contents--
|
|
|
|
```jsx
|
|
class MyComponent extends React.Component {
|
|
constructor(props) {
|
|
super(props);
|
|
}
|
|
componentWillMount() {
|
|
// Change code below this line
|
|
|
|
// Change code above this line
|
|
}
|
|
render() {
|
|
return <div />
|
|
}
|
|
};
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```jsx
|
|
class MyComponent extends React.Component {
|
|
constructor(props) {
|
|
super(props);
|
|
}
|
|
componentWillMount() {
|
|
// Change code below this line
|
|
console.log('Component is mounting...');
|
|
// Change code above this line
|
|
}
|
|
render() {
|
|
return <div />
|
|
}
|
|
};
|
|
```
|