React native 为什么我需要导出组件以将其传递给registerComponent方法？

此代码工作正常：

import React, { Component } from 'react';
import { Text, AppRegistry } from 'react-native';

export default class App extends Component {
  render() {
    return (
      <Text>Hello World!</Text>
    );
  }
}

AppRegistry.registerComponent('SampleApp', () => App);

---

需要导出某些内容，以便稍后由其他脚本导入

根据MDN：

export语句用于创建JavaScript模块，从模块中导出函数、对象或原语值，以便其他程序使用import语句

---

我猜registerComponent方法需要一个模块作为参数之一。

您遇到了哪一个错误？您是如何导入模块的？还要将

'SampleApp'

修复到

'SampleApp'

中我将错误消息添加到我的帖子中。此外，打字错误是固定的。

import React, { Component } from 'react';
import { Text, AppRegistry } from 'react-native';

class App extends Component {
  render() {
    return (
      <Text>Hello World!</Text>
    );
  }
}

AppRegistry.registerComponent('SampleApp', () => App);

Invariant Violation: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: object. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.

Check the render method of `ExpoRootComponent`.

This error is located at:
    in RootErrorBoundary (at registerRootComponent.js:34)
    in ExpoRootComponent (at renderApplication.js:33)
    in RCTView (at View.js:60)
    in View (at AppContainer.js:102)
    in RCTView (at View.js:60)
    in View (at AppContainer.js:122)
    in AppContainer (at renderApplication.js:32)

throwOnInvalidElementType
    ReactNativeRenderer-dev.js:4705:2
createFiberFromElement
    ReactNativeRenderer-dev.js:4663:16
reconcileSingleElement
    ReactNativeRenderer-dev.js:8337:22
reconcileChildFibers
    ReactNativeRenderer-dev.js:8421:12
reconcileChildrenAtExpirationTime
    ReactNativeRenderer-dev.js:8621:29
finishClassComponent
    ReactNativeRenderer-dev.js:8839:4
updateClassComponent
    ReactNativeRenderer-dev.js:8761:11
beginWork
    ReactNativeRenderer-dev.js:9580:15
performUnitOfWork
    ReactNativeRenderer-dev.js:12924:15