编辑2：在使用robertklep的建议之后我仍然得到信息 - 未处理的socket.io url错误，但我现在也得到“GET /socket.io/socket.io.js 404 3.325 ms - 1257”现在
Error: Can't set headers after they are sent.
at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:335:11)
at ServerResponse.header (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/response.js:718:10)
at ServerResponse.contentType (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/response.js:551:15)
at ServerResponse.send (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/response.js:138:14)
at done (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/response.js:957:10)
at View.exports.renderFile [as engine] (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/ejs/lib/ejs.js:355:10)
at View.render (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/view.js:126:8)
at tryRender (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/application.js:639:10)
at EventEmitter.render (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/application.js:591:3)
at ServerResponse.render (/Users/actuallywilliam/Desktop/Work/Websites/Click the Button/node_modules/express/lib/response.js:961:7)
编辑结束
我正在this上尝试my website教程，但我遇到了这个错误：
info - unhandled socket.io url
我正在使用Socket.io版本0.9.10（因为它说在教程中使用该版本）。
这是我的HTML：
<meta charset="utf-8" />
<title>Draw</title>
<!-- The stylesheets -->
<link rel="stylesheet" href="../assets/css/styles.css" />
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<!--[if lt IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
</head>
<body>
<div id="body">
<center>
<h1>Draw <a href="draw-changelog" id="version">Indev</a></h1>
<p><a id="tip">tip</a>: refresh the page to clear the canvas!</p>
<p>made by <a href="aboutme">William</a> - <a href="https://twitter.com/williamsthing">@williamsthing</a> / <a href="https://ello.co/972">@972</a>. inspired by <a href="http://flockdraw.com">flockdraw</a>. <a id="version" href="draw-changelog">v1.0</a>.</p>
</center>
</div>
<div id="cursors">
<!-- The mouse pointers will be created here -->
</div>
<canvas id="paper" width="1900" height="1000">
Your browser needs to support canvas for this to work!
</canvas>
<!--<script src="socketio/node_modules/socket.io-client/dist/socket.io.js"></script> !-->
<script src="socketio/node_modules/socket.io-client/dist/socket.io.js"></script>
<script src="http://code.jquery.com/jquery-1.8.0.min.js"></script>
<script id="drawing" src="../assets/js/script.js"></script>
</body>
这是我的script.js：
$(function(){
// This demo depends on the canvas element
if(!('getContext' in document.createElement('canvas'))){
alert('Sorry, it looks like your browser does not support canvas!');
return false;
}
// The URL of your web server (the port is set in app.js)
var url = 'http://localhost:8080';
var doc = $(document),
win = $(window),
canvas = $('#paper'),
ctx = canvas[0].getContext('2d'),
instructions = $('#instructions');
// Generate an unique ID
var id = Math.round($.now()*Math.random());
// A flag for drawing activity
var drawing = false;
var clients = {};
var cursors = {};
var socket = io.connect();
socket.sockets.on('moving', function (data) {
if(! (data.id in clients)){
// a new user has come online. create a cursor for them
cursors[data.id] = $('<div class="cursor">').appendTo('#cursors');
}
// Move the mouse pointer
cursors[data.id].css({
'left' : data.x,
'top' : data.y
});
// Is the user drawing?
if(data.drawing && clients[data.id]){
// Draw a line on the canvas. clients[data.id] holds
// the previous position of this user's mouse pointer
drawLine(clients[data.id].x, clients[data.id].y, data.x, data.y);
}
// Saving the current client state
clients[data.id] = data;
clients[data.id].updated = $.now();
});
var prev = {};
canvas.on('mousedown',function(e){
e.preventDefault();
drawing = true;
prev.x = e.pageX;
prev.y = e.pageY;
// Hide the instructions
instructions.fadeOut();
});
doc.bind('mouseup mouseleave',function(){
drawing = false;
});
var lastEmit = $.now();
doc.on('mousemove',function(e){
if($.now() - lastEmit > 30){
socket.emit('mousemove',{
'x': e.pageX,
'y': e.pageY,
'drawing': drawing,
'id': id
});
lastEmit = $.now();
}
// Draw a line for the current user's movement, as it is
// not received in the socket.on('moving') event above
if(drawing){
drawLine(prev.x, prev.y, e.pageX, e.pageY);
prev.x = e.pageX;
prev.y = e.pageY;
}
});
// Remove inactive clients after 10 seconds of inactivity
setInterval(function(){
for(ident in clients){
if($.now() - clients[ident].updated > 10000){
// Last update was more than 10 seconds ago.
// This user has probably closed the page
cursors[ident].remove();
delete clients[ident];
delete cursors[ident];
}
}
},10000);
function drawLine(fromx, fromy, tox, toy){
ctx.moveTo(fromx, fromy);
ctx.lineTo(tox, toy);
ctx.stroke();
}
});
最后，这是我的app.js：
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var routes = require('./routes/index');
var users = require('./routes/users');
var cors = require('cors')
var app = express();
var app_serv = require('http').createServer(handler),
io = require('socket.io').listen(app_serv),
static = require('node-static'); // for serving files
var allowCrossDomain = function(req, res, next) {
res.header('Access-Control-Allow-Origin', "*");
};
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/socketio', express.static(__dirname + '/node_modules/socket.io'));
app.use('/', routes);
app.use('/users', users);
app.use(cors());
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handlers
// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: err
});
});
}
// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
res.status(err.status || 500);
res.render('error', {
message: err.message,
error: {}
});
});
module.exports = app;
// This will make all the files in the current folder
// accessible from the web
var fileServer = new static.Server('./');
// This is the port for our web server.
// you will need to go to http://localhost:8080 to see it
app_serv.listen(8080);
// If the URL of the socket server is opened in a browser
function handler (request, response) {
request.addListener('end', function () {
fileServer.serve(request, response);
});
}
// Listen for incoming connections from clients
io.sockets.on('connection', function (socket) {
// Start listening for mouse move events
socket.on('mousemove', function (data) {
// This line sends the event (broadcasts it)
// to everyone except the originating client.
socket.broadcast.emit('moving', data);
});
});
编辑：我也在控制台中获得这一行： GET /socket.io/1/?t=1439497344004 404 6.084 ms - 1257 我也可能需要帮助。
答案 0 :(得分：1)
您的应用设置有问题，您似乎正在混合Express和非Express部件。
要设置Express应用，请使用以下命令：
app_serv并删除与fileServer和app.use('/socketio', express.static(__dirname + '/node_modules/socket.io'));
相关的所有内容，因为您不需要它。
同时删除此内容：
<script src="socketio/node_modules/socket.io-client/dist/socket.io.js"></script>
改变这个：
<script src="/socket.io/socket.io.js"></script>
对此：
var App = angular.module('MyApp', ['MyApp.filters', 'MyApp.services', 'MyApp.directives', 'ui.bootstrap']);