【发布时间】：2016-02-21 02:54:13
【问题描述】：
在这里，我将数据从 app.js 发送到 index.html 页面。但我没有得到异步数据。
这里我正在尝试下载文件并尝试将下载进度发送到 index.html。但是在“index.html”中，下载完成后我正在获取数据。我不想要这会发生。
如果文件下载了 40%，那么浏览器中也会显示相同的内容。我该如何实现呢？谁能帮帮我...
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 fs = require('fs');
var request = require('request');
var progress = require('request-progress');
var DOWNLOAD_DIR = '/usr/local/';
var file_name = 'jquery.js'
var routes = require('./routes/index');
var users = require('./routes/users');
var app = express ();
var http = require('http').createServer(app);
var io = require('socket.io')(http);
http.listen(8085, function(){
console.log('listening on *:8085');
});
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(__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('/', routes);
app.use('/users', users);
app.get('/get', function (req, res) {
progress(request('https://jqueryjs.googlecode.com/files/jquery-1.3.2-vsdoc2.js'), {
throttle:0,
delay: 0
})
.on('progress', function(state){
console.log('received size in bytes', state.received);
console.log('total size in bytes', state.total);
console.log('percent', state.percent);
io.of('/socket_issue').on('connection', function (socket) {
console.log("Socket connected :"+socket.id);
socket.emit('message', JSON.stringify({size: state.total, received: state.received, percent: state.percent, fileName: file_name}));
});
})
.pipe(fs.createWriteStream(DOWNLOAD_DIR + file_name))
.on('error', function (err) {
console.log("error");
})
.on('close', function (err){
console.log("Download Complete");
});
res.sendfile('views/index.html');
});
// 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;
我的 index.html ：
<html>
<body>
<script src="http://localhost:8085/javascripts/socket.js"></script>
<script src="https://code.jquery.com/jquery-1.10.2.js"></script>
<script src="http://localhost:8085/javascripts/bootstrap.js"></script>
<script src="http://localhost:8085/javascripts/bootstrap-progressbar.js"></script>
<script src="http://code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
<link href="http://code.jquery.com/ui/1.10.4/themes/ui-lightness/jquery-ui.css" rel="stylesheet">
<link rel="stylesheet" type="text/css" href="http://localhost:8085/stylesheets/bootstrap.css" />
<div id="progressbar"><div>
<script type="text/javascript">
var socket = io('http://localhost:8085/socket_issue');
socket.on('connect', function(){ console.log('connected to socket'); });
socket.on('error', function(e){ console.log('error' + e); });
socket.on('message', function(data){
console.log(data);
function progress(percent, $element) {
var progressBarWidth = percent * $element.width() / 100;
$element.find('div').animate({ width: progressBarWidth }, 500).html(percent + "% ");
}
progress(JSON.parse(data).percent, $('#progressbar'));
});
socket.on('disconnect', function(){});
</script>
</body>
</html>
在 index.html 中（已编辑）
<body onload="timedRefresh(10000);">
<script type="text/javaScript">
function timedRefresh(timeoutPeriod) {
setTimeout("window.location.reload(true);",timeoutPeriod);
}
</script>
【问题讨论】：
标签： node.js asynchronous socket.io