实例中用到了(实例在Windows XP下运行)：Node.js、Socket.IO、Express.js、jade、stylus

先在hosts文件中添加两行规则，关于两个子域的：sub1.localhost、sub2.localhost

使用socket.io

1: var exp = require('express');

       2: var app = exp.createServer();

       3:  

       4: global.socket = require('socket.io').listen(app);

       5: global.socket.set('log level', 1);

       6: global.socket.set('transports', [ 'websocket', 'flashsocket', 'htmlfile', 'xhr-polling', 'jsonp-polling']);

加载配置，创建子域的应用

1: app.use(exp.vhost('sub1.' + global.host, require('./subdomains/sub1')));

       2: app.use(exp.vhost('sub2.' + global.host, require('./subdomains/sub2')));

       3:  

       4: require('./app/config')(app, exp);

       5: require('./app/server/router')(app);

       6: require('./app/server/modules/chat-socket');

chat-socket.js模块

1: module.exports = function() {

       2:         

       3:     global.socket.of('/chat').on('connection', function(socket) { 

       4:        //todo 

       5:     });

       6: }();

前台页面使用socket.io.js建立连接

1: socket = io.connect('/chat');

       2: socket.on('status', function (connections) {

       3:     

       4: });

       5: socket.on('user-ready', function (data) {

       6:     

       7: });

       8: socket.on('user-message', function (data) {

       9:     

      10: });

      11:  

      12: socket.on('user-disconnected', function (data) {

      13:     

      14: });

      15:  

      16: //向后台发送消息

      17: socket.emit('user-ready', {name : 'xxx'});

运行完整的示例node app.js即可，下载示例源码>>

本文参考：

1、http://www.quietless.com/kitchen/building-a-node-js-chat-application-and-sharing-socket-io-across-multiple-subdomains/

2、creating-a-basic-site-with-node-and-express