* 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>
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id, title, challengeType, forumTopicId, dashedName
id | title | challengeType | forumTopicId | dashedName |
---|---|---|---|---|
5a24c314108439a4d4036170 | 創建一個有狀態的組件 | 6 | 301391 | create-a-stateful-component |
--description--
React 中最重要的主題之一是 state
。 state 包含應用程序需要了解的任何數據,這些數據可能會隨時間而變化。 應用程序能夠響應 state 的變更,並在必要時顯示更新後的 UI。 React 爲現代 Web 應用程序的狀態管理提供了一個很好的解決方案。
可以在類組件的 constructor
上聲明 state
屬性來在 React 組件中創建 state, 它在創建時使用 state
初始化組件。 state
屬性必須設置爲 JavaScript object
(對象)。 聲明如下:
this.state = {
}
可以在組件的整個生命週期內訪問 state
對象, 可以更新它、在 UI 中渲染它,也可以將其作爲 props 傳遞給子組件。 state
對象的使用可以很簡單,亦可以很複雜,就看你怎麼用了。 請注意,必須通過擴展 React.Component
來創建類組件,以便像這樣創建 state
。
--instructions--
代碼編輯器中有一個組件試圖從其 state
中渲染一個 name
屬性, 但是 state
還沒有定義。 在 constructor
中使用 state
初始化組件,並將你的名字賦給 name
屬性。
--hints--
StatefulComponent
應該存在並被渲染。
assert(
(function () {
const mockedComponent = Enzyme.mount(
React.createElement(StatefulComponent)
);
return mockedComponent.find('StatefulComponent').length === 1;
})()
);
StatefulComponent
應該渲染一個 div
元素和一個 h1
元素。
assert(
(function () {
const mockedComponent = Enzyme.mount(
React.createElement(StatefulComponent)
);
return (
mockedComponent.find('div').length === 1 &&
mockedComponent.find('h1').length === 1
);
})()
);
應使用被設置爲字符串的 name
屬性來初始化 StatefulComponent
的 state。
assert(
(function () {
const mockedComponent = Enzyme.mount(
React.createElement(StatefulComponent)
);
const initialState = mockedComponent.state();
return (
typeof initialState === 'object' && typeof initialState.name === 'string'
);
})()
);
StatefulComponent
中 state 的 name
屬性應該渲染在 h1
元素裏。
assert(
(function () {
const mockedComponent = Enzyme.mount(
React.createElement(StatefulComponent)
);
const initialState = mockedComponent.state();
return mockedComponent.find('h1').text() === initialState.name;
})()
);
--seed--
--after-user-code--
ReactDOM.render(<StatefulComponent />, document.getElementById('root'))
--seed-contents--
class StatefulComponent extends React.Component {
constructor(props) {
super(props);
// Only change code below this line
// Only change code above this line
}
render() {
return (
<div>
<h1>{this.state.name}</h1>
</div>
);
}
};
--solutions--
class StatefulComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
name: 'freeCodeCamp!'
}
}
render() {
return (
<div>
<h1>{this.state.name}</h1>
</div>
);
}
};