express上的node.js找不到模型

在我的路由器文件中有一个post方法，我在其中实例化了联系人模型中的一个对象。但我对联系人模型的定义不明确。错误是

错误：

**TypeError: Cannot read property 'firstname' of undefined**

routes/contact.js

var express = require('express');
var router = express.Router();

var Contact = require("../models/contacts");

router.post('/contact', function(req, res, next) {
   res.send("POST method");
    newContact = new Contact({
      firstname: req.body.firstname,
      lastname: req.body.lastname
   }

var mongoose = require('mongoose');
var Schema = mongoose.Schema;

var contactSchema = new Schema({
  firstname:  String,
  lastname: String
});

var Contact = module.exports = mongoose.model('Contact', contactSchema);

models/contacts.js

var express = require('express');
var router = express.Router();

var Contact = require("../models/contacts");

router.post('/contact', function(req, res, next) {
   res.send("POST method");
    newContact = new Contact({
      firstname: req.body.firstname,
      lastname: req.body.lastname
   }

var mongoose = require('mongoose');
var Schema = mongoose.Schema;

var contactSchema = new Schema({
  firstname:  String,
  lastname: String
});

var Contact = module.exports = mongoose.model('Contact', contactSchema);

---

你的模型是正确的。您必须使用主体解析器来解析请求主体

见：

在routes/contact.js中添加以下代码

var bodyParser = require('body-parser')
router.use(bodyParser.urlencoded({ extended: false }))
router.use(bodyParser.json())