编译 ./src/App 失败.js尝试导入错误：'UserProvider'未从'./model/UserContext'导出

Question

我收到以下错误，如果有人能指出我正确的方向，我会很高兴:)

编译 ./src/App 失败.js尝试导入错误："用户提供程序" 不会从"./model/UserContext"导出。

用户上下文.js

const UserProvider = ({  children, history}) => { ... })
export default withRouter(UserProvider);

应用.js

import React from 'react';
import NavBar from './components/navBar';
import Login from './components/login';
import Session from './components/session';
import Dashboard from './components/dashboard';
import './App.css';
import Container from '@material-ui/core/Container';
import {BrowserRouter as Router, Route, Switch} from 'react-router-dom';
import { UserProvider } from './model/UserContext'

function App() {
return (
<div>
<UserProvider>
<Session />
<NavBar />
<Container maxWidth="sm">
<Router>
<Route path='/Login' component={Login}  />
<Route path='/Dashboard' component={Dashboard}  />
</Router>
</Container>
</UserProvider>
</div>
);
}
export default App;

Answer 1

您正在将用户提供程序导出为默认值。所以在应用程序中.js只需像下面这样导入(不带大括号(。

import UserProvider from './model/UserContext'

Answer 2

import { UserProvider } from './model/UserContext'

你需要这样写：

import UserProvider from './model/UserContext'