React Redux Uncaught錯誤：期望reducer是一個函數

Question

我正在學習React並嘗試使用Redux設置React時遇到問題。 我在createStore上得到這個錯誤：

未捕獲的錯誤：期望減速器具有功能

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;
    }
}

我已經看到其他類似的問題，但是似乎沒有一個問題可以解決我的問題。

Answer 1

如果要導入操作方式，則需要導出default ：

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

否則，您可以像這樣導入：

import { movieReducer } from './reducers';