Question

我收到以下错误，该错误使用Node.js和socket.io运行服务器。

错误

C:\Users\황진우\Desktop\nodejstest>node app2
Server Running at http://127.0.0.1:52273
Missing error handler on `socket`.
TypeError: Cannot read property 'timerID' of undefined
    at Socket.<anonymous> (C:\Users\황진우\Desktop\nodejstest\app2.js:97:27)
    at emitOne (events.js:77:13)
    at Socket.emit (events.js:169:7)
    at Socket.onevent (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\lib\socket.js:335:8)
    at Socket.onpacket (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\lib\socket.js:295:12)
    at Client.ondecoded (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\lib\client.js:193:14)
    at Decoder.Emitter.emit (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\node_modules\socket.io-parser\node_modules\component-emitter\index.js:134:20)
    at Decoder.add (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\node_modules\socket.io-parser\index.js:247:12)
    at Client.ondata (C:\Users\황진우\Desktop\nodejstest\node_modules\socket.io\lib\client.js:175:18)
    at emitOne (events.js:77:13)

代码如下。

服务器端app2.js

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


var counter = 0;
function Product(name, image, price, count){
    this.index = counter++;
    this.name = name; 
    this.image = image;
    this.price = price;
    this.count = count;
};

var products = [
    new Product('JavaScript','chrome.png', 28000 , 30 ),
    new Product('jQuery','chrome.png',28000 , 30),
    new Product('Node.js','chrome.png', 32000, 30),
    new Product('Socket.io','chrome.png', 17000, 30),
    new Product('Connect','chrome.png', 18000, 30),
    new Product('Express','chrome.png', 31000, 30),
    new Product('EJS','chrome.png', 12000, 30)
];


var app = express();
var server = http.createServer(app);


app.use(express.static(__dirname+'/public'));


app.route('/').get(function(req,res){

    var HTMLPage = fs.readFileSync('HTMLPage2.html','utf-8');


    res.send(ejs.render(HTMLPage,{
        products : products
    }));
});


server.listen(52273, function(){
    console.log('Server Running at http://127.0.0.1:52273');
});


var io = require('socket.io').listen(server);
io.sockets.on('connection', function(socket){

    function onReturn(index){

        products[index].count++;


        clearTimeout(cart[index].timerID);


        delete cart[index];


        io.sockets.emit('count', {
            index : index,
            count : products[index].count
        });
    };


    var cart = {};


    socket.on('cart',function(index){

        products[index].count--;


        cart[index] = {};
        cart[index].index = index;
        cart[index].timerID = setTimeout(function(){
            onReturn(index);
        }, 1000*5);


        io.sockets.emit('count',{
            index : index,
            count : products[index].count
        });
    });





    socket.on('buy', function(index){

        clearTimeout(cart[index].timerID);


        delete cart[index];


        io.sockets.emit('count', {
            index: index,
            count: products[index].count
        });
    });


    socket.on('return', function(index){
        onReturn(index);
    });
});

客户端HTMLPage2.HTML

<!DOCTYPE html>
<html>
    <head>

        <meta name="viewport" content="width=device-width, initial-scale=1" />
        <script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
        <link rel="stylesheet" href="http://code.jquery.com/mobile/1.3.1/jquery.mobile-1.3.1.min.css" />
        <script src="http://code.jquery.com/mobile/1.3.1/jquery.mobile-1.3.1.min.js"></script>
        <script src="/socket.io/socket.io.js"></script>
        <script>
            $(document).ready(function() {

                function changeIcon(parent, from, to){
                    var target = $('.ui-btn-text', parent).next();
                    target.removeClass(from).addClass(to);
                }

                function changeCount(index, count){
                    $('li[data-index = '+index + '] .ul-li-count').html(count);
                }

                var socket = io.connect();


                socket.on('count', function(data){

                    changeCount(data.index, data.count);
                });

                $('.product > a[data-icon]').click(function(){
                    if($(this).attr('toggle') != 'off'){

                        var index = $(this).attr('data-index');


                        socket.emit('cart', Number(index));


                        changeIcon(this, 'ui-icon-check', 'ui-icon-back');


                        $(this).attr('toggle', 'off');

                    }else{

                        var index = $(this).attr('data-index');

                        if(confirm('물건을 구매하겠습니까?')){

                            socket.emit('buy',Number(index));


                            $(this).parent().remove();
                            $('#listview').listview('refresh');
                        }else{

                            socket.emit('return',Number(index));


                            changeIcon(this, 'ui-icon-back','ui-icon-check');
                        }

                        $(this).attr('toggle','on');
                    }
                });

            });
        </script>
    </head>
    <body>
        <div data-role = "page">
            <div data-role = "header">
                <h1>Store</h1>
            </div>
            <div data-role="content">
                <ul id="listview" data-role="listview" data-insert="true" data-filter="true">
                <li data-role="list-divider">products</li>
                <% products.forEach(function (item, index) { %>
                <li class="product" data-index="<% item.index %>">
                    <a href="#">
                        <img src="chrome.png" />
                        <h3><%= item.name %></h3>
                        <p><%= item.price %>원</p>
                        <span class="ul-li-count"><%= item.count %></span>
                    </a>
                    <a href="#" data-icon="check" data-index="<%= item.index %>"></a>
                </li>
                <% }); %>
                </ul>
            </div>
            </div>          
    </body>

</html>

我在这一行得到错误。 'clearTimeout（车[指数] .timerID）;'

请帮我解决此错误。

Answer 1

当用户想要直接购买商品而不将其放在购物车上时，会触发此错误。在这种情况下，永远不会触发cart事件，因此cart[index]永远不会存在。

socket.on('buy', function(index){

    if(cart[index]){

        clearTimeout(cart[index].timerID);


        delete cart[index];
    }

    io.sockets.emit('count', {
        index: index,
        count: products[index].count
    });
});

此外，您应该像这样处理错误事件：

socket.on('error',function(er){
    console.log(er);
});

获取缺少的错误处理程序套接字消息，无法使用Node.js和Socket.io

1 个答案: