TypeError：.find（…）不是函数nodejs mongoose

我正在处理nodejs中的样本。 我碰到TypeError：Cars.find（…）是不是在D：\ Karthikeyan \rest服务器\路线\ carsRouter.js 19:15当我尝试访问http：// localhost：3000 /汽车 。 谢谢App.js

var express = require('express'); var path = require('path'); var favicon = require('serve-favicon'); var logger = require('morgan'); var cookieParser = require('cookie-parser'); var bodyParser = require('body-parser'); var mongoose = require('mongoose'); var url = 'mongodb://localhost:27017/myTest'; mongoose.connect(url); var db = mongoose.connection; db.on('error',console.error.bind(console,'Connection error')); db.once('open',function(){ console.log("connected to db server"); }); var routes = require('./routes/index'); var users = require('./routes/users'); var carsRouter = require('./routes/carsRouter'); var app = express(); // view engine setup app.set('views', path.join(__dirname, 'views')); app.set('view engine', 'jade'); // uncomment after placing your favicon in /public //app.use(favicon(path.join(__dirname, 'public', 'favicon.ico'))); app.use(logger('dev')); app.use(bodyParser.json()); app.use(bodyParser.urlencoded({ extended: false })); app.use(cookieParser()); app.use(express.static(path.join(__dirname, 'public'))); app.use('/', routes); app.use('/users', users); app.use('/cars',carsRouter); // catch 404 and forward to error handler app.use(function(req, res, next) { var err = new Error('Not Found'); err.status = 404; next(err); }); // error handlers // development error handler // will print stacktrace if (app.get('env') === 'development') { app.use(function(err, req, res, next) { res.status(err.status || 500); res.render('error', { message: err.message, error: err }); }); } // production error handler // no stacktraces leaked to user app.use(function(err, req, res, next) { res.status(err.status || 500); res.render('error', { message: err.message, error: {} }); }); module.exports = app; 

路线/ carsRouter.js

 var express = require('express'); var bodyParser = require('body-parser'); /*Parses the data seerved from client*/ var mongoose = require('mongoose'); var Cars = require('../models/cars'); var carsRouter = express.Router(); /*with the help we have defined in global with router*/ carsRouter.use(bodyParser.json()); carsRouter.route('/') .get(function(req,res,next){ Cars.find({})(function (err,cars) { assert.equal(err,null); res.json(cars); }); }) .post(function(req,res,next){ Cars.create(req.body,function(err,cars){ if(err) throw err; console.log('cars inserted'); var id = cars._id; res.writeHead(200,{'content-type':'text/plain'}); res.end('the car you inserted is '+id); }); }) .delete(function(req,res,next){ Cars.remove({},function(err,res){ if(err) throw err; res.json(res); }); }); carsRouter.route('/:carId') .get(function(req,res,next){ Cars.findById(req.params.id,function(err,cars){ if(err) throw err; res.json(cars); }); }) .put(function(req,res,next){ Cars.findByIdAndUpdate(req.params.id,{ $set:req.body }, { new:true },function(err,cars){ if(err) throw err; res.json(cars); }); }) .delete(function(req,res,next){ Cars.remove(req.params.id,function(err,res){ if(err) throw err; res.json(res); }); }); carsRouter.route('/:carId/comments') .get(function(req,res,next){ Cars.findById(req.params.id,function(err,cars){ if(err) throw err; res.json(cars.comments); }); }) .post(function(req,res,next){ Cars.findById(req.params.id,function(err,cars){ if(err) throw err; cars.comments.push(req.body); cars.save(function (err,cars) { if(err) throw err; console.log('updated'); res.json(cars); }); res.json(cars.comments); }); }) .delete(function(req,res,next){ Cars.findById(req.params.id,function(err,cars){ if(err) throw err; for (var i = (cars.comments.length - 1); i >= 0; i--){ cars.comments.id(cars.comments[i]._id).remove(); } cars.save(function (err,cars) { if(err) throw err; console.log('updated'); res.json(cars); }); }); Cars.remove(req.params.id,function(err,res){ res.writeHead(200,{'content-type':'text/plain'}); res.end('comments deleted'); }); }); module.exports = carsRouter; 

车型/ cars.js

 var mongoose = require('mongoose'); var Schema = mongoose.Schema; var commentsSchema = new Schema({ rating:{ type:Number, min:1, max:5, required:true }, comment:{ type:String, required:true }, price:{ type:String, required:true } }, { timestamps:true }); var carsSchema = new Schema({ name:{ type: String, required:true, unique:true }, description:{ type:String, required:true }, comments:[commentsSchema] }, {timestamps:true}); var cars = mongoose.model('cars',carsSchema); module.exports = cars; 

Answer 1

你已经用错误的方式使用find query ， callback必须在find函数中

  carsRouter.route('/') .get(function(req, res, next) { Cars.find({}, function(err, cars) { assert.equal(err, null); res.json(cars); }); }); 

Answer 2

您发现的查询是错误的。

更新它像：

 Cars.find({}, function (err,cars) { assert.equal(err,null); res.json(cars); }); 

要么

 Cars.find({}) .exec(function (err,cars) { assert.equal(err,null); res.json(cars); });