javascript - Socket.io : "Cannot read property ' emit' of undefined"

Question

所以我目前正在使用 socket.io 开发我的网站。

今天，当我实现套接字时，我遇到了一个不错的小错误“无法读取未定义的属性'emit'”我找不到我的代码有什么问题，所以我希望你们能帮助我。

App.js:

var socket  = require( 'socket.io' );
var express = require('express');
var app     = express();
var server  = require('http').createServer(app);
var io      = socket.listen( server );
var port    = 9999;

server.listen(port, function () {
  console.log('Listening at port %d', port);
});

io.sockets.on('connection', function (socket) {
    console.log('User connected');

    socket.on('create_socket', function(port){
    console.log(port);
});

客户端:

<div>
    <p class="connected" hidden>Connected port : 9999</p>
    <p class="connect_error" hidden><strong>Can not connect to socket on port 9999</strong></p>
</div>

<script>
    var socket = io.connect("http://localhost:9999");

    // If connection can not be established
    socket.on('connect_error', function(socket) {
        $('.connected').hide();
        $('.connect_error').show();
    });

    // Connection established
    socket.on('connect', function(socket) {
        $('.connect_error').hide();
        $('.connected').show();
       // socket.on('create_socket', null, <?= $port; ?> );
       socket.emit('create_socket', '<?= $port; ?>');
    });
</script>

顺便说一句，所有的 socket.io/jquery/... 包含都正确完成，即使它们没有出现在代码中

提前致谢

Answer 1

客户端代码:

改变

// Connection established
    socket.on('connect', function(socket) {

至

// Connection established
    socket.on('connect', function(data) {

最终:

// Connection established
    socket.on('connect', function(data) {
        $('.connect_error').hide();
        $('.connected').show();
       console.log(data);
       socket.emit('create_socket', '<?= $port; ?>');
    });

之前，您覆盖了套接字对象。