43 lines
1.2 KiB
Markdown
43 lines
1.2 KiB
Markdown
---
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title: Pass State as Props to Child Components
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localeTitle: 将状态作为道具传递给子组件
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---
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## 将状态作为道具传递给子组件
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在这个挑战中，我们将传递状态，但由于状态是其父组件的本地，我们必须使用**props**传递给子组件。在子组件中使用props将允许我们将所有状态数据保存在父组件中，并且我们可以将数据沿一个方向传递给子组件。
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```javascript
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class MyApp extends React.Component {
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constructor(props) {
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super(props);
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this.state = {
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name: 'CamperBot'
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}
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}
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render() {
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return (
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<div>
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// Here we will call this.state.name in order to pass the value of CamperBot
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// to the NavBar component
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<Navbar name={this.state.name} />
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</div>
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);
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}
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};
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class Navbar extends React.Component {
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constructor(props) {
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super(props);
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}
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render() {
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return (
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<div>
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// Since we passed in the CamperBot state value into the the NavBar component above
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// the h1 element below will render the value passed from state
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<h1>Hello, my name is: {this.props.name}</h1>
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</div>
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);
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}
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};
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``` |