reactjs - 类型错误 : Cannot read property ‘getState’ of undefined

Question

我想尝试小的 redux 示例，所以我安装了 redux，但出现此错误

TypeError: Cannot read property ‘getState’ of undefined

new Provider webpack-internal:///./node_modules/react-redux/es/components/Provider.js:24:25

代码:

import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';

import './index.css';

const App = () => (<div>Hi </div>);

ReactDOM.render(<Provider><App /></Provider>, document.getElementById('root'));

怎么了 ？

Answer 1

如果我们往里面看 react-redux <Provider />
<Provider />预计会提供 store支柱:

this.state = {
  storeState: store.getState(),
                   ^^here
  store
}

因此错误。

但是，您可以使用 reducer 创建一个，应该类似于以下内容:

import React from 'react'
import { render } from 'react-dom'
import { Provider } from 'react-redux'
import { createStore } from 'redux'
import reducer from './reducer'
import App from './components/App'

const store = createStore(reducer)

render(
  <Provider store={store}>
    <App />
  </Provider>,
  document.getElementById('root')
)