我有一个接受子代的组件，我想做的就是将子代的数量限制为一个，我希望该子代是反应本机中的单个视图或单个文本
答案 0 :(得分：1)
您可以使用React.Children API，特别是ABCs-Mac-mini-6:ServiceProviderApp ABCEDFC$ react-native bundle --entry-file index.js --platform ios --dev false --bundle-output ios/main.jsbundle --assets-dest ios
Loading dependency graph, done.
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While trying to resolve module `react-navigation-stack` from file `/Users/ABCEDFC/Desktop/react-native/New folder/ServiceProviderApp/node_modules/react-navigation/src/react-navigation.js`, the package `/Users/ABCEDFC/Desktop/react-native/New folder/ServiceProviderApp/node_modules/react-navigation/node_modules/react-navigation-stack/package.json` was successfully found. However, this package itself specifies a `main` module field that could not be resolved (`/Users/ABCEDFC/Desktop/react-native/New folder/ServiceProviderApp/node_modules/react-navigation/node_modules/react-navigation-stack/dist/index.js`. Indeed, none of these files exist:
* `/Users/ABCEDFC/Desktop/react-native/New folder/ServiceProviderApp/node_modules/react-navigation/node_modules/react-navigation-stack/dist/index.js(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json|.ios.ts|.native.ts|.ts|.ios.tsx|.native.tsx|.tsx)`
* `/Users/ABCEDFC/Desktop/react-native/New folder/ServiceProviderApp/node_modules/react-navigation/node_modules/react-navigation-stack/dist/index.js/index(.native||.ios.js|.native.js|.js|.ios.json|.native.json|.json|.ios.ts|.native.ts|.ts|.ios.tsx|.native.tsx|.tsx)`
。
我相信正确的语法是：
React.Children.only这将验证只有一个孩子，然后返回该孩子，或者如果有多个孩子，则抛出错误。
您也可以使用class MyComponent extends React.Component {
render(){
return React.Children.only(this.props.children)()
}
}
PropTypes如果您想进一步证明自己的孩子只是一个class MyComponent extends React.Component {
render(){
const children = this.props.children
return (
<>
{children}
</>
)
}
}
MyComponent.propTypes = {
children: PropTypes.element.isRequired
}
或Text实例，则可以编写一个自定义PropTypes validator，这里是一个example on StackOverflow