reactjs - 在react js中应用applyMiddleware(thunk)时获取 "Cannot call a class as a function"

Question

这是我的index.js 文件代码 -

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';
import './index.css';
import { BrowserRouter as Router, Route } from 'react-router-dom'; 
import { Provider } from 'react-redux';
import thunk from 'react-thunk';
import { createStore, applyMiddleware } from 'redux';
import Login from './Components/LoginRegister';

const store= createStore(
        (state = {}) => state, 
        applyMiddleware(thunk)
    );

ReactDOM.render(( 
    <Provider store={store}>
      <Router>
        <switch>
            <Route exact path="/" component={App} />
            <Route path="/Loginregister" component={Login} />
        </switch>
      </Router>
    </Provider>  ),
  document.getElementById('root')
);

当我将“applyMiddleware”中的“thunk”传递为“applyMiddleware(thunk)”时，我在控制台上收到以下错误 -

Uncaught TypeError: Cannot call a class as a function
    at _classCallCheck (index.js:15)
    at ReactThunk (index.js:36)
    at applyMiddleware.js:51
    at createStore (createStore.js:65)
    at Object.<anonymous> (index.js:11)
    at __webpack_require__ (bootstrap b42575b…:555)
    at fn (bootstrap b42575b…:86)
    at Object.<anonymous> (bootstrap b42575b…:578)
    at __webpack_require__ (bootstrap b42575b…:555)
    at bootstrap b42575b…:578

请让我知道我做错了什么。

Answer 1

您正在导入

import thunk from 'react-thunk';

但是 thunk 来自 redux-thunk 模块。

所以你应该导入

import thunk from 'redux-thunk';

此外，我认为您对“createStore”的调用会有问题。

createStore 采用一个 reducer (或组合 reducer )和可能的中间件。

reducer 接受一个状态和一个操作，并且必须返回存储的新状态。

function reducer(state, action){

  // Switch-Case for action.type
  // Copy the current state and apply changes

  return state;
}