31 lines
607 B
Markdown
31 lines
607 B
Markdown
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---
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title: Override Default Props
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localeTitle: 覆盖默认道具
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---
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## 覆盖默认道具
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此挑战使您可以覆盖Items组件的props `quantity`的默认值。其中， `quantity`默认值设置为`0` 。
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```react.js
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const Items = (props) => {
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return <h1>Current Quantity of Items in Cart: {props.quantity}</h1>
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}
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Items.defaultProps = {
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quantity: 0
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}
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```
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要覆盖默认的props值，要遵循的语法是
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```react.js
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<Component propsName={Value}/>
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```
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在语法之后，应在给定代码下面声明以下代码
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```react.js
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<Items quantity={50}/>
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```
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这将覆盖值`0`到`50`
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