如何从mongodb中获取数据并使用nodeJS将其传输到Html页面？

我试图从mongodb中获取数据并将其作为json格式发送到html页面

我的代码是：

server.js

var express = require("express"), app = express(), bodyParser = require('body-parser'), errorHandler = require('errorhandler'), methodOverride = require('method-override'), hostname = process.env.HOSTNAME || 'localhost', port = parseInt(process.env.PORT, 10) || 4004, publicDir = process.argv[2] || __dirname + '/public'; var exec = require('child_process').exec; var fs = require('fs'); var MongoClient = require('mongodb').MongoClient , format = require('util').format; //Show homepage app.get("/", function (req, res) { res.redirect("/index.html"); console.log("shubham "); }); app.get("/index/", function (req, res) { res.redirect("/index.html"); console.log("shubham "); }); app.get("/search", function (req, res){ console.log("shubham batra"); var pro_name = req.query.name; var pro_code = req.query.code; var pro_category = req.query.category; var pro_brand = req.query.brand; var products; MongoClient.connect('mongodb://127.0.0.1:27017/prisync', function(err, db) { if (err) throw err; console.log("Connected to Database"); var documen = {name:pro_name, code:pro_code , category:pro_category, brand:pro_brand }; //insert record db.collection('urlinfo').insert(documen, function(err, records) { if (err) throw err; } var products = db.collection('urlinfo').find({}); //line 48 ====== console.log(products); res.json(products); }); db.close(); }); console.log(res.body); }); app.use(errorHandler({ dumpExceptions: true, showStack: true })); //Search page app.use(methodOverride()); app.use(bodyParser.json()); app.use(bodyParser.urlencoded({ extended: true })); app.use(express.static(publicDir)); app.use(errorHandler({ dumpExceptions: true, showStack: true })); console.log("Server showing %s listening at http://%s:%s", publicDir, hostname, port); app.listen(port); 

那么它会产生以下错误：

 /home/shubham/Music/server/server.js:48 var products = db.collection('urlinfo').find({}); ^^^ SyntaxError: Unexpected token var at Module._compile (module.js:439:25) at Object.Module._extensions..js (module.js:474:10) at Module.load (module.js:356:32) at Function.Module._load (module.js:312:12) at Function.Module.runMain (module.js:497:10) at startup (node.js:119:16) at node.js:935:3 

Answer 1

如下所述改变你的第48行。 db.collection.find(不会返回数据，一旦db.collection.find({})函数被执行，它将进入callback函数db.collection.find（{}， callback ）

 db.collection('urlinfo').find({}, function(err, products){ if(err){ console.log(err); res.json(err); } else{ res.json(products); } });