Router.use()需要一个中间件函数,但未定义

Router.use() requires a middleware function but got undefined(Router.use()需要一个中间件函数,但未定义)
本文介绍了Router.use()需要一个中间件函数,但未定义的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我想使用NodeJS制作身份验证应用程序,但得到类似标题的错误:(

但是app.js的代码已经是这样的

var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var session = require('express-session')

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(session({ 
  secret: '123456cat',
  resave: false,
  saveUninitialized: true,
  cookie: { maxAge: 60000 }
}))
app.use(express.static(path.join(__dirname, 'public')));

var registrationRouter = require('./routes/registration-route').default;
var loginRouter = require('./routes/login-route').default;
var dashboardRouter = require('./routes/dashboard-route').default;
var logoutRouter = require('./routes/logout-route');

app.use('/', registrationRouter);
app.use('/', loginRouter);
app.use('/', dashboardRouter);
app.use('/', logoutRouter);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

app.listen(3000);

module.exports = app;

这是register-route.js

var express = require('express');
var router = express.Router();
var db = require('../database');

// to display registration form 
router.get('/register', function(req, res, next) {
  res.render('registration-form');
});

// to store user input detail on post request
router.post('/register', function(req, res, next) {
    
    inputData ={
        username: req.body.username,
        email_address: req.body.email_address,
        password: req.body.password,
        confirm_password: req.body.confirm_password
    }
// check unique email address
var sql='SELECT * FROM registration WHERE email_address =?';
    db.query(sql, [inputData.email_address] ,function (err, data, fields) {
 if(err) throw err
 if(data.length>1){
     var msg = inputData.email_address+ "was already exist";
 }else if(inputData.confirm_password != inputData.password){
    var msg ="Password & Confirm Password is not Matched";
 }else{
     
    // save users data into database
    var sql = 'INSERT INTO registration SET ?';
   query(sql, inputData, function (err, data) {
      if (err) throw err;
           });
  var msg ="Your are successfully registered";
 }
 res.render('registration-form',{alertMsg:msg});
})
     
});
module.exports = router;

login-route.js

var express = require('express');
var router = express.Router();
var db = require('../database');
/* GET users listing. */
router.get('/login', function(req, res, next) {
  res.render('login-form');
});

router.post('/login', function(req, res){
    var email = req.body.email;
    var password = req.body.password;

    var sql='SELECT * FROM registration WHERE email_address =? AND password =?';
    db.query(sql, [email, password], function (err, data, fields) {
        if(err) throw err
        if(data.length>0){
            req.session.loggedinUser= true;
            req.session.email= email;
            res.redirect('/dashboard');
        }else{
            res.render('login-form',{alertMsg:"Your Email Address or password is wrong"});
        }
    })

})

module.exports = router;

logout-route.js

var express = require('express');
var router = express.Router();
/* GET users listing. */
router.get('/logout', function(req, res) {
  req.session.destroy();
  res.redirect('/login');
});
module.exports = router;

dashboard-route.js

var express = require('express');
var router = express.Router();
/* GET users listing. */
router.get('/dashboard', function(req, res, next) {
    if(req.session.loggedinUser){
        res.render('dashboard',{email:req.session.emailAddress})
    }else{
        res.redirect('/login');
    }
});
module.exports = router;
我已经看到这样的问题,但没有一个答案适用于我的案例问题 另外,我也尝试过npm clear cache --force,但没有任何变化

也已为node_modulespackage-lock卸载并重新安装,但始终出现相同的错误

推荐答案

全部更改:

var registrationRouter = require('./routes/registration-route').default;

要删除.default,您只需执行以下操作:

const registrationRouter = require('./routes/registration-route');

.default用于ESM模块,而不用于CommonJS模块。


此外,您不应该再使用var。它现在是绝对的了。对这些使用const

这篇关于Router.use()需要一个中间件函数,但未定义的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持编程学习网!

本站部分内容来源互联网,如果有图片或者内容侵犯您的权益请联系我们删除!

相关文档推荐

Update another component when Formik form changes(当Formik表单更改时更新另一个组件)
Formik validation isSubmitting / isValidating not getting set to true(Formik验证正在提交/isValiating未设置为True)
React Validation Max Range Using Formik(使用Formik的Reaction验证最大范围)
Validation using Yup to check string or number length(使用YUP检查字符串或数字长度的验证)
Updating initialValues prop on Formik Form does not update input value(更新Formik表单上的初始值属性不会更新输入值)
password validation with yup and formik(使用YUP和Formick进行密码验证)