javascript - react Redux 未捕获错误 : Expected the reducer to be a function

Question

我正在学习 React，在尝试使用 Redux 设置 React 时遇到了问题。我在使用 createStore 时遇到此错误:

Uncaught Error: Expected the reducer to be a function

index.js

import React from 'react';
import {render} from 'react-dom';
import {Provider} from 'react-redux';
import {createStore, applyMiddleware, compose} from 'redux';
import movieReducer from './reducers';
import App from './App';
import dataService from './services/dataService';

let store = createStore(movieReducer, {}, applyMiddleware(dataService));

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

reducers.js

export const movieReducer = (state = {}, action) => {
    switch (action.type){
        case 'GET_MOVIE_RECEIVED':
            return action.data;
        default:
            return state;
    }
}

我见过其他类似的问题，但似乎都没有解决我的问题。

Answer 1

如果你想导入你正在做的方式，你需要导出default:

export default (state = {}, action) => {
    switch (action.type){
        case 'GET_MOVIE_RECEIVED':
            return action.data;
        default:
            return state;
    }
}

否则，您可以这样导入:

import { movieReducer } from './reducers';