36 lines
604 B
Markdown
36 lines
604 B
Markdown
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---
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title: Use Default Props
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localeTitle: 使用默认道具
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---
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## 使用默认道具
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这个挑战让您宣布ShoppingCart组件的默认道具
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```javascript
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const ShoppingCart = (props) => {
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return (
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<div>
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<h1>Shopping Cart Component</h1>
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</div>
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)
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};
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```
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要声明默认道具，要遵循的语法是
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```javascript
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itemName.defaultProps = {
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prop-x: value,
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prop-y: value
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}
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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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```javascript
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ShoppingCart.defaultProps = {
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items: 0
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}
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```
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这声明了一个名为'items'的道具，其值为'0'。
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