NodeJS ReferenceError：io未定义

我开始在节点JS和面临一个问题与io lib，这里的错误：

ReferenceError: io is not defined at exports.index (D:\dev\lib\index.js:9:5) at callbacks (D:\dev\node_modules\express\lib\router\index.js:164:37) at param (D:\dev\node_modules\express\lib\router\index.js:138:11) at pass (D:\dev\node_modules\express\lib\router\index.js:145:5) at Router._dispatch (D:\dev\node_modules\express\lib\router\index.js:1 73:5) at Object.router (D:\dev\node_modules\express\lib\router\index.js:33:1 0) at next (D:\dev\node_modules\express\node_modules\connect\lib\proto.js:190:15) at Object.methodOverride [as handle] (D:\dev\node_modules\express\node_modules\connect\lib\middleware\methodOverride.js:49:5) at next (D:\dev\node_modules\express\node_modules\connect\lib\proto.js:190:15) at Object.urlencoded [as handle] (D:\dev\node_modules\express\node_modules\connect\lib\middleware\urlencoded.js:51:37) 

这里是我的app.js文件的内容：

 var express = require('express'); var path = require('path'); var app = express(), server = require('http').createServer(app), io = require('socket.io').listen(server), fs = require('fs'); app.set('port', process.env.PORT || 8080); 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(express.static(path.join(__dirname, 'public'))); app.get('/', require('./lib').index); server.listen(app.get('port'), function(){ console.log('Express server listening on port ' + app.get('port')); }); 

我的文件lib / index.js：

 exports.index = function(req, res){ res.render('index'); io.sockets.on('connection', function (socket) { socket.emit('message', 'welcome'); }); }; 

有人可以帮助我吗？

Answer 1

您需要将io传递给您的路线：

 exports.index = function(io) { return function(req,res) { res.render('index'); io.sockets.on('connection', function (socket) { socket.emit('message', 'welcome'); } } } 

然后在app.get调用它作为一个函数：

 app.get('/', require('./lib').index(io)); 

我build议使用其他variables声明require('./lib')部分。 这将允许代码重用和更好的可读性（这是相对于每个人）。

 var /*other variables*/, lib = require('./lib'); 

然后你可以做app.get('/', lib.index(io));

只是一个想法。