Javascript TypeError:无法读取属性'；名称'；未定义节点的定义
我是NodeJS的新手，我正在尝试为一家汽车租赁公司制作一个后端API。我已经将“name”的类型定义为string，而且我也没有在请求中传递空字符串，那么为什么它会显示此错误？几天以来我一直在寻找解决方案，但在互联网上的任何地方都找不到答案。我在某个地方读到mongoose的旧版本有一个bug，所以我在更新它之后也尝试了，但是错误没有发生，并且还尝试了更新到最新的NodeJS版本 这是我的密码 index.jsJavascript TypeError:无法读取属性'；名称'；未定义节点的定义,javascript,node.js,mongodb,express,mongoose,Javascript,Node.js,Mongodb,Express,Mongoose,我是NodeJS的新手，我正在尝试为一家汽车租赁公司制作一个后端API。我已经将“name”的类型定义为string，而且我也没有在请求中传递空字符串，那么为什么它会显示此错误？几天以来我一直在寻找解决方案，但在互联网上的任何地方都找不到答案。我在某个地方读到mongoose的旧版本有一个bug，所以我在更新它之后也尝试了，但是错误没有发生，并且还尝试了更新到最新的NodeJS版本 这是我的密码 index.js let express = require('express'); let a
let express = require('express');
let app = express();
let mongoose = require('mongoose');
var port = process.env.PORT || 8081
let bodyparser = require('body-parser');
const { urlencoded } = require('body-parser');
app.use(bodyparser.urlencoded(
{
extended: true
}))
app.use(bodyparser.json());
var apiRoutes = require('./routes');
app.use('/api', apiRoutes);
const dbPath = "mongodb://localhost/carrentalagencypractice"
const options = {useNewUrlParser:true, useUnifiedTopology:true}
const mongo = mongoose.connect(dbPath,options)
mongo.then(()=>{
console.log('Connected to mongodb')
} ,error=> {console.log(error,'error')})
app.use('/', function(req, res){
res.send('Welcome to Car Rental Agency')
});
app.listen(port, ()=>{
console.log('Running on port '+port)
});
let router = require('express').Router();
router.get('/', function(req, res){
res.json({
status: 'API works',
message: 'Welcome to Car Rental Agency services'
})
})
var carController = require('./carController')
var userController = require('./userController')
router.route('/car').get(carController.index).post(carController.add)
router.route('/user').get(userController.index).post(userController.add)
router.route('/car/car_id').get(carController.view).patch(carController.update).put(carController.update).delete(carController.delete)
router.route('/user/user_id').get(userController.index).patch(userController.update).put(userController.update).delete(userController.delete)
module.exports = router
var mongoose = require('mongoose')
var carSchema = new mongoose.Schema({
name:{
type: String,
required: true
},
brand:{
type: String,
required: true
},
price:{
type: String,
required: true
},
capacity:{
type: String,
required:true
}
});
var Car = module.exports = mongoose.model('car',carSchema);
module.exports.get = function(callback, limit){
Car.find(callback).limit(limit);
}
var mongoose = require('mongoose')
var userSchema = new mongoose.Schema({
name:{
type: String,
required: true
},
email:{
type: String,
required: true
},
phone:{
type: String,
required: true
},
address:{
type: String,
required: true
}
})
var User = module.exports = mongoose.model('user', userSchema)
module.exports.get = function(callback, limit){
User.find(callback).limit(limit);
}
User = require("./userModel");
exports.index = function(req, res){
User.get(function(err, user){
if(err)
res.send(err)
res.json({
status: "Got all user details successfully",
message: user
})
})
}
exports.add = function(req, res){
User.add(function(err, user){
var user = new User()
if(err)
res.send(err)
user.name = req.body.name ? req.body.name : user.name;
user.email = req.body.email;
user.address = req.body.address;
user.phone = req.body.phone;
res.json({
status: "User details are successfully added",
message: user
})
})
}
exports.view = function(req, res){
User.findByID(req.params.user_id, function(err, user){
if(err)
res.send(err)
res.json({
status: "Successfully retreived user details",
message: user
})
})
}
exports.update = function(req, res){
User.findById(req.params.user_id, function(err, user){
if(err)
res.send(err)
user.name = req.body.name? req.body.name: user.name;
user.email = req.body.email;
user.address = req.body.address;
user.phone = req.body.phone;
user.save(function(req, res){
if(err)
res.send(err)
res.json({
status: "User details updated successfully",
message: user
})
})
}
)
}
exports.delete = function(req, res){
User.deleteOne(req.params.user_id, function(err, user){
if(err)
res.send(err)
res.json({
status: "success",
message: "The user account has been deleted"
})
})
}
Car = require('./carModel');
exports.index = function(req, res){
Car.get(function(err, car){
if(err)
res.json({
status: "error",
message: err
})
res.json({
status: "successfull",
message: "Car details succesfully retreived",
data: car
})
});
}
exports.add = function(req, res){
var car = new Car();
car.name = res.body.name ? req.body.name : car.name;
car.brand = res.body.brand;
car.price = res.body.price;
car.capacity = res.body.capacity;
car.save(function(err){
if(err)
res.json(err);
console.log
res.json({
status: "successfull",
message: "Successfully add new car details"
})
})
}
exports.view = function(req, res){
Car.findById(req.params.car_id, function(err, car){
if(err)
res.send(err)
res.json({
status: "Car details",
message: car
})
})
}
exports.update = function(req, res){
Car.findById(req.params.car_id, function(err, car){
if(err)
res.send(err)
car.name = req.body.name? req.body.name: car.name;
car.price = req.body.price;
car.brand = req.body.brand;
car.capacity = req.body.capacity;
car.save(function(err){
if(err)
res.send(err)
res.json({
status:"Car details updated successfully",
message: car
})
})
})
}
exports.delete = function(req, res){
Car.deleteOne({
_id: car_id
}, function(err, contact){
if(err)
res.send(err)
res.json({
status: "success",
message:"Car ad deleted"
})
}
)
}
User = require("./userModel");
exports.index = function(req, res){
User.get(function(err, user){
if(err)
res.send(err)
res.json({
status: "Got all user details successfully",
message: user
})
})
}
exports.add = function(req, res){
User.add(function(err, user){
var user = new User()
if(err)
res.send(err)
user.name = req.body.name ? req.body.name : user.name;
user.email = req.body.email;
user.address = req.body.address;
user.phone = req.body.phone;
res.json({
status: "User details are successfully added",
message: user
})
})
}
exports.view = function(req, res){
User.findByID(req.params.user_id, function(err, user){
if(err)
res.send(err)
res.json({
status: "Successfully retreived user details",
message: user
})
})
}
exports.update = function(req, res){
User.findById(req.params.user_id, function(err, user){
if(err)
res.send(err)
user.name = req.body.name? req.body.name: user.name;
user.email = req.body.email;
user.address = req.body.address;
user.phone = req.body.phone;
user.save(function(req, res){
if(err)
res.send(err)
res.json({
status: "User details updated successfully",
message: user
})
})
}
)
}
exports.delete = function(req, res){
User.deleteOne(req.params.user_id, function(err, user){
if(err)
res.send(err)
res.json({
status: "success",
message: "The user account has been deleted"
})
})
}
Car = require('./carModel');
exports.index = function(req, res){
Car.get(function(err, car){
if(err)
res.json({
status: "error",
message: err
})
res.json({
status: "successfull",
message: "Car details succesfully retreived",
data: car
})
});
}
exports.add = function(req, res){
var car = new Car();
car.name = res.body.name ? req.body.name : car.name;
car.brand = res.body.brand;
car.price = res.body.price;
car.capacity = res.body.capacity;
car.save(function(err){
if(err)
res.json(err);
console.log
res.json({
status: "successfull",
message: "Successfully add new car details"
})
})
}
exports.view = function(req, res){
Car.findById(req.params.car_id, function(err, car){
if(err)
res.send(err)
res.json({
status: "Car details",
message: car
})
})
}
exports.update = function(req, res){
Car.findById(req.params.car_id, function(err, car){
if(err)
res.send(err)
car.name = req.body.name? req.body.name: car.name;
car.price = req.body.price;
car.brand = req.body.brand;
car.capacity = req.body.capacity;
car.save(function(err){
if(err)
res.send(err)
res.json({
status:"Car details updated successfully",
message: car
})
})
})
}
exports.delete = function(req, res){
Car.deleteOne({
_id: car_id
}, function(err, contact){
if(err)
res.send(err)
res.json({
status: "success",
message:"Car ad deleted"
})
}
)
}
TypeError: Cannot read property 'name' of undefined
at exports.add (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\carController.js:26:25)
at Layer.handle [as handle_request] (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\layer.js:95:5)
at next (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\route.js:137:13)
at next (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\route.js:131:14)
at Route.dispatch (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\route.js:112:3)
at Layer.handle [as handle_request] (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\layer.js:95:5)
at C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:281:22
at Function.process_params (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:335:12)
at next (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:275:10)
at Function.handle (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:174:3)
at router (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:47:12)
at Layer.handle [as handle_request] (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\layer.js:95:5)
at trim_prefix (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:317:13)
at C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:284:7
at Function.process_params (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:335:12)
at next (C:\Work\NodeJS Practice\Car Rental Agency (Practice)\node_modules\express\lib\router\index.js:275:10)
在carController.js中
exports.add=函数（req，res）{
var car=新车（）；
car.name=req.body.name？req.body.name：car.name；
car.brand=req.body.brand；
car.price=所需车身价格；
car.capacity=req.body.capacity；car.name = res.body.name ? req.body.name : car.name;
car.name = req.body.name ? req.body.name : car.name;
在最后四行中，我已将res替换为req，我已在答案中解释，请再次检查。当然，如果您有任何其他问题，请告诉我