38 lines
750 B
Markdown
38 lines
750 B
Markdown
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---
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title: Render Conditionally from Props
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localeTitle: 从道具有条理地渲染
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---
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## 从道具有条理地渲染
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这是一个有点棘手的挑战，但很容易。
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## 解
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使用适当的增量声明更改`handleClick()` 。
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```react.js
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handleClick() {
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this.setState({
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counter: this.state.counter + 1
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});
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}
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```
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在`render()`方法中，使用质询描述中提到的`Math.random()`并编写三元表达式以在**Results**组件中传递`props` 。
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```react.js
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let expression = Math.random() > .5;
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{(expression == 1)? <Results fiftyFifty="You win!"/> : <Results fiftyFifty="You lose!"/> }
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```
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然后在Results组件中渲染`fiftyFifty`道具。
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```react.js
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<h1>
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{
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this.props.fiftyFifty
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}
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</h1>
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```
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