javascript - TypeError: Router.use() 需要一个中间件函数，但得到一个对象 nodejs

Question

我正在制作一个登录系统nodejs api，但是当我添加注册路线时，它给了我一些这样的错误，我正在使用 express@^4.16

C:\projects\mernapp\backend\node_modules\express\lib\router\index.js:458
      throw new TypeError('Router.use() requires a middleware function but got a ' + gettype(fn))
      ^

TypeError: Router.use() requires a middleware function but got a Object
    at Function.use (C:\projects\mernapp\backend\node_modules\express\lib\router\index.js:458:13)
    at Function.<anonymous> (C:\projects\mernapp\backend\node_modules\express\lib\application.js:220:21)
    at Array.forEach (<anonymous>)
    at Function.use (C:\projects\mernapp\backend\node_modules\express\lib\application.js:217:7)
    at Object.<anonymous> (C:/projects/mernapp/backend/src/app.js:18:5)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    at loader (C:\projects\mernapp\backend\node_modules\babel-register\lib\node.js:144:5)
    at Object.require.extensions.(anonymous function) [as .js] (C:\projects\mernapp\backend\node_modules\babel-register\lib\node.js:154:7)
    at Module.load (internal/modules/cjs/loader.js:599:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
    at Function.Module._load (internal/modules/cjs/loader.js:530:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:742:12)
    at Object.<anonymous> (C:\projects\mernapp\backend\node_modules\babel-cli\lib\_babel-node.js:154:22)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
    at Module.load (internal/modules/cjs/loader.js:599:32)
[nodemon] app crashed - waiting for file changes before starting...

我确实谷歌了这个错误，我也在stackoverflow上发现了一些问题，但这没有用。 Router.use() 需要一个中间件函数，但有一个未定义的

这是我的代码 app.js

import auth from './routes/auth';
import user from './routes/user';
const app = express();

app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

app.use('/api/auth', auth);
app.use('/api/user', user);

路线/注册

import express from 'express';
import bcrypt from 'bcrypt';
import validateRegisterInput from '../validation/register';
import User from '../models/User';

const router = express.Router();

router.post('/register', function (req, res){
    const { errors, isValid } = validateRegisterInput(req.body);
    if(!isValid) {
        return res.status(400).json(errors);
    }
    User.findOne({
        email: req.body.email
    }).then(user => {
        if (user) {
            return res.status(400).json({
                email: 'Email already exists'
            });
        } else {
            const newUser = new User({
                firstname: req.body.firstname,
                lastName: req.body.lastname,
                email: req.body.email,
                password: req.body.password
            });
            bcrypt.genSalt(10, (err, salt) => {
                if (err) console.error('There was an error', err);
                else {
                    bcrypt.hash(newUser.password = hash);
                    newUser
                        .save().then(user => {
                            res.json(user)
                        });
                }
            })
        }
    })
})

标签： javascriptnode.jsexpress