55 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			55 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: 5a24c314108439a4d4036168
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								title: Write a React Component from Scratch
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								challengeType: 6
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								isRequired: false
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								videoUrl: ''
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								localeTitle: 从Scratch写一个React组件
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								---
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								## Description
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								<section id="description">现在您已经学习了JSX和React组件的基础知识,现在是时候自己编写一个组件了。 React组件是React应用程序的核心构建块,因此非常熟悉编写它们非常重要。请记住,典型的React组件是扩展<code>React.Component</code>的ES6 <code>class</code> 。它有一个返回HTML(来自JSX)或<code>null</code>的render方法。这是React组件的基本形式。一旦你理解了这一点,你就会准备开始构建更复杂的React项目。 </section>
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								## Instructions
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								<section id="instructions">定义一个扩展<code>React.Component</code>的类<code>MyComponent</code> 。它的render方法应该返回一个<code>div</code> ,其中包含一个带有文本的<code>h1</code>标签: <code>My First React Component!</code>在里面。准确使用此文本,案例和标点符号很重要。确保也调用组件的构造函数。使用<code>ReactDOM.render()</code>将此组件呈现给DOM。有一个<code>div</code> , <code>id='challenge-node'</code>可供您使用。 </section>
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								## Tests
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								<section id='tests'>
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								```yml
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								tests:
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								  - text: 应该有一个名为<code>MyComponent</code>的React组件。
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								    testString: 'getUserInput => assert(getUserInput("index").replace(/\s/g, "").includes("classMyComponentextendsReact.Component{"), "There should be a React component called <code>MyComponent</code>.");'
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								  - text: <code>MyComponent</code>应该包含带有文本<code>My First React Component!</code>的<code>h1</code>标签<code>My First React Component!</code>案例和标点符号问题。
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								    testString: 'assert((function() { const mockedComponent = Enzyme.mount(React.createElement(MyComponent)); return mockedComponent.find("h1").text() === "My First React Component!"; })(), "<code>MyComponent</code> should contain an <code>h1</code> tag with text <code>My First React Component!</code> Case and punctuation matter.");'
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								  - text: <code>MyComponent</code>应该呈现给DOM。
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								    testString: 'assert(document.getElementById("challenge-node").childNodes.length === 1, "<code>MyComponent</code> should render to the DOM.");'
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								```
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								</section>
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								## Challenge Seed
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								<section id='challengeSeed'>
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								<div id='jsx-seed'>
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								```jsx
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								// change code below this line
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								```
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								</div>
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								</section>
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								## Solution
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								<section id='solution'>
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								```js
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								// solution required
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								```
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								</section>
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