通过socket.id向客户端发送消息

您的代码存在一些问题，首先是您不应该通过Socket.IO对用户进行身份验证，您应该确保用户只有在经过身份验证后才能进行连接。如果您使用的是Express，则以下文章可以为您提供很多帮助：http : //www.danielbaulig.de/socket-
ioexpress/

另外，您应该避免像这样发送消息，因为它在内部是Socket.IO的一部分，并且可能会更改：

io.sockets.socket(id).emit('hello');

相反（如果您想向特定客户端发送消息），最好保留一个对象，例如与连接的客户端（并在断开连接时删除客户端）：

// the clients hash stores the sockets// the users hash stores the username of the connected user and its socket.idio.sockets.on('connection', function (socket) {  // get the handshake and the session object  var hs = socket.handshake;  users[hs.session.username] = socket.id; // connected user with its socket.id  clients[socket.id] = socket; // add the client data to the hash  ...  socket.on('disconnect', function () {    delete clients[socket.id]; // remove the client from the array    delete users[hs.session.username]; // remove connected user & socket.id  });}// we want at some point to send a message to user 'alex'if (users['alex']) {  // we get the socket.id for the user alex  // and with that we can sent him a message using his socket (stored in clients)  clients[users['alex']].emit("Hello Alex, how've you been");}

当然，

io.sockets.socket(id)

您可能希望在客户端代码中更改的另一件事是

var socket = io.connect('');

var socket =io.connect('http://localhost');