Socket.io 不是从客户端或服务器发出?

Socket.io not Emitting from Client nor Server?

在客户端,我有这个代码:

var serverAddress = "http://localhost:8081";
var socket = io(serverAddress);

socket.on('connect', function(){
    console.log("Connected to server on %s", serverAddress);
});
socket.emit("xxx", {text : "attack"});

在服务器上,我有这个:

var express = require('express');
var http = require('http');

var app = express();
var server = http.createServer(app);
var socket = require('socket.io').listen(server);

socket.on('connect', function() {
    console.log('A user is connected to server');
});
socket.on('xxx', function(data) {
    console.log(data);
});

connect 事件被触发并在服务器上被捕获,但 xxx 事件甚至没有被触发或被捕获。怎么了? Console.log没有报错。

您混淆了 socket.io 服务器 与 socket.io 连接

建立新的客户端连接时,服务器接收到 connection 事件。该事件的参数(通常称为 socket)表示该连接。这是您需要用来收听消息的对象:

// server
...
var io = require('socket.io').listen(server);
...
io.on('connection', function(socket) {
  console.log('A user is connected to server');
  socket.on('xxx', function(data) {
    console.log(data);
  });
});