在node.js上使用socket-io的Http服务器没有运行

我在node.js上使用socket-io的http服务器没有运行。我使用npm install socket-io和运行服务器。

服务器的代码

    var static = require('node-static');
var http = require('http');
// Create a node-static server instance
var file = new(static.Server)();
// We use the http moduleÕs createServer function and
// rely on our instance of node-static to serve the files
var app = http.createServer(function (req, res) {
  file.serve(req, res);
}).listen(8181);
// Use socket.io JavaScript library for real-time web applications
var io = require('socket.io').listen(app);
// Let's start managing connections...
io.sockets.on('connection', function (socket){
        // Handle 'message' messages
        socket.on('message', function (message) {
                log('S --> got message: ', message);
                // channel-only broadcast...
                socket.broadcast.emit('message', message);
        });
        // Handle 'create or join' messages
        socket.on('create or join', function (room) {
                /*var namespace = '/';
                for (var numClients in io.nsps[namespace].adapter.rooms[room]) {
                    console.log(numClients);
                }*/
                //var numClients = io.sockets.clients(room).length;
                var numClients = io.sockets.adapter.rooms[room]!=undefined ? Object.keys(io.sockets.adapter.rooms[room]).length:0;
                log('SERVER: CLIENTS ' + room + ' has ' + numClients + ' client(s)');
                log('S --> Room ' + room + ' has ' + numClients + ' client(s)');
                log('S --> Request to create or join room', room);
                // First client joining...
                if (numClients == 0){
                        socket.join(room);
                        socket.emit('created', room);
                } else if (numClients == 1) {
                // Second client joining...                 
                        io.sockets.in(room).emit('join', room);
                        socket.join(room);
                        socket.emit('joined', room);
                        log('S: sent JOIN message');
                } else { // max two clients
                        socket.emit('full', room);
                }
        });
        function log(){
            var array = [">>> "];
            for (var i = 0; i < arguments.length; i++) {
                array.push(arguments[i]);
            }
            socket.emit('log', array);
        }
});

当这是客户端连接到套接字的代码:

   var room = getParameterByName('room_name'); 
alert ("room_name: "+room);
// Connect to signalling server
var socket = io.connect();
// Send 'Create or join' message to singnalling server
if (room !== '') {
  console.log('Create or join room', room);
  socket.emit('create or join', room);
}

使用netstat -a命令，我看到了服务器的端口是活动的。但是它不发送消息。

我有另一个问题:服务器如何发送消息不广播，但指定的对等连接?我的意思是:而不是

socket.on('message', function (message) {
            log('S --> got message: ', message);
            // channel-only broadcast...
            socket.broadcast.emit('message', message);
    });

我该怎么办?谢谢!