Node.js和mongodb TypeError：undefined不是一个函数
我是node.js和mongodb的新手。 我正在使用快递和玉来testing我正在写的应用程序。 我configuration了mongodb和node.js，但是当我尝试从数据库中检索数据时，出现以下错误： TypeError: undefined is not a function
/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/base.js:242 throw message; ^ TypeError: undefined is not a function at commandHandler (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/cursor.js:706:16) at /Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/db.js:1806:9 at Server.Base._callHandler (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/base.js:442:41) at /Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/server.js:485:18 at MongoReply.parseBody (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/responses/mongo_reply.js:68:5) at null.<anonymous> (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/server.js:443:20) at EventEmitter.emit (events.js:95:17) at null.<anonymous> (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:191:13) at EventEmitter.emit (events.js:98:17) at Socket.<anonymous> (/Users/apple/Documents/Nodejs/NODE/express_example/node_modules/mongodb/lib/mongodb/connection/connection.js:418:22)
这是我的代码：这是负责提取数据的用户列表路由。
exports.userlist = function(db) { return function(req, res) { var collection = db.get('usercollection'); collection.find({},{},function(e,docs){ res.render('userlist', { "userlist" : docs }); }); }; };
这里是userlist.jade文件：
extends layout block content h1. User List ul each user, i in userlist li a(href="mailto:#{user.email}")= user.username
这里是我调用userlist，即app.js的代码
/** * Module dependencies. */ var express = require('express'); var routes = require('./routes'); var user = require('./routes/user'); var http = require('http'); var path = require('path'); var mongo = require('mongodb'); var monk = require('monk'); var db = monk('localhost:27017/nodetest1'); var app = express(); // all environments app.set('port', process.env.PORT || 3000); app.set('views', path.join(__dirname, 'views')); app.set('view engine', 'jade'); app.use(express.favicon()); app.use(express.logger('dev')); app.use(express.json()); app.use(express.urlencoded()); app.use(express.methodOverride()); app.use(app.router); app.use(require('stylus').middleware(path.join(__dirname, 'public'))); app.use(express.static(path.join(__dirname, 'public'))); // development only if ('development' == app.get('env')) { app.use(express.errorHandler()); } app.get('/', routes.index); app.get('/users', user.list); app.get('/helloworld', routes.helloworld); app.get('/userlist', routes.userlist(db)); http.createServer(app).listen(app.get('port'), function(){ console.log('Express server listening on port ' + app.get('port')); });
如果您尝试修改find方法，该怎么办？
exports.userlist = function(db) { return function(req, res) { var collection = db.get('usercollection'); collection.find().toArray(function(e,docs){ res.render('userlist', { "userlist" : docs }); }); }; };