使用 Node.js 和 Socket.io 获取丢失的错误处理程序套接字消息

Question

您好，我收到以下错误，使用 Node.js 和 socket.io 运行服务器。

错误：

Missing error handler on `socket`.
TypeError: Cannot read property 'connected' of undefined
    at Socket.<anonymous> (C:\Documents and Settings\Subhrajyoti\Desktop\Restore
\htdocs\video broadcast\server.js:68:13)
    at Socket.emit (events.js:95:17)
    at Socket.onevent (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\htd
ocs\video broadcast\node_modules\socket.io\lib\socket.js:330:8)
    at Socket.onpacket (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\ht
docs\video broadcast\node_modules\socket.io\lib\socket.js:290:12)
    at Client.ondecoded (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\h
tdocs\video broadcast\node_modules\socket.io\lib\client.js:193:14)
    at Decoder.Emitter.emit (C:\Documents and Settings\Subhrajyoti\Desktop\Resto
re\htdocs\video broadcast\node_modules\socket.io\node_modules\socket.io-parser\n
ode_modules\component-emitter\index.js:134:20)
    at Decoder.add (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\htdocs
\video broadcast\node_modules\socket.io\node_modules\socket.io-parser\index.js:2
47:12)
    at Client.ondata (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\htdo
cs\video broadcast\node_modules\socket.io\lib\client.js:175:18)
    at Socket.emit (events.js:95:17)
    at Socket.onPacket (C:\Documents and Settings\Subhrajyoti\Desktop\Restore\ht
docs\video broadcast\node_modules\socket.io\node_modules\engine.io\lib\socket.js
:99:14)

我的服务器端代码如下。

Server.js：

var port=8888;
var express=require('express');
var morgan = require('morgan');
var http=require('http');
var bodyParser= require('body-parser');
var methodOverride = require('method-override');
var mongo = require('mongojs');
var database='Oditek';
var collections=['video'];
var app= express();
var server=http.Server(app);
var io=require('socket.io')(server);
var db = mongo.connect("127.0.0.1:27017/"+database, collections);
app.use(express.static(__dirname + '/public'));     // set the static files location /public/img will be /img for users
app.use(morgan('dev'));                     // log every request to the console
app.use(bodyParser.urlencoded({ extended: false }))    // parse application/x-www-form-urlencoded
app.use(bodyParser.json())    // parse application/json
app.use(methodOverride());                  // simulate DELETE and PUT
db.on('ready', function () {
    console.log('database connected')
});
app.get('/',function(req,res){
    res.sendfile('view/login.html');
});
app.post('/login',function(req,res){
    var username=req.body.username;
    var password=req.body.userpassword;
    if(username && password){
        db.video.findOne({
            username:username,
            password:password
        },function(err,doc){
            if(doc){
                console.log('login',doc);
                res.send(doc);
            }
            if(err){
                console.log('login12',err);
                res.send("could not login");
            }
        });
    }
});
app.get('/video',function(req,res){
    res.sendfile('view/video.html');
});

//socket----programming//
var roomid;
var clients={};
io.sockets.on('connection',function(socket){
    //console.log(socket);
    roomid=socket.handshake.query.roomid;
    var usertype=socket.handshake.query.usertype;
    socket.on('admin-join',function(data){
        console.log('admin',data);
        if(data.IsJoinAdmin){
            clients={
                "socket":roomid
            }
            socket.join(roomid);
        }
    });
    socket.on('user-join',function(data){
        console.log('user',data);
        if(data.isUserJoin){
            io.socket.connected[clients.socket].emit('user-already-joined',data);
            socket.join(roomid);
        }
    });
    socket.on('send-broadcasting-message',function(data){
        console.log('message',data)
        io.to(roomid).emit('sending-broadcasting',data);
    });

});
server.listen(port);
console.log('server is listening on the port'+port);

我在io.socket.connected[clients.socket].emit('user-already-joined',data);这一行收到错误。我正在使用此行向特定用户发送私人消息。请帮助我解决此错误。

Answer 1

您的错误被抛出，因为 io 对象没有属性套接字，但它具有属性 sockets。所以你应该这样写：

io.sockets.connected[clients.socket].emit('user-already-joined',data);

如果您使用 socket.io 1.0 有更好的方法来做到这一点。每个 socket 都会通过 self id 自动加入一个默认房间。

因此您可以使用以下代码通过 id 向套接字发出：

io.to(clients.socket).emit('user-already-joined',data);

Answer 2

查看server.js 的第 68 行并对其进行注释，您将看到您使用的是在套接字范围内定义的公式。