用PHP5.2+APC实现超酷的PHP进度条_人生进度条php-优快云博客

英文原文（并非按词一个个译过来的)

http://martinjansen.com/2007/04/upload-progress/

这里是Rasmus Lerdorf实现的一个利用php5.2的新特性来进行上传进度条的例子。
为了让php存储并显示文件上传进度，他利用了APC来实现内存级缓存。APC最新的版本有一个特性（虽然没有文档化），一旦开启，将会监听包含 APC_UPLOAD_PROGRESS的表单的文件上传进度。一旦发现这个POST变量，APC将会创建一个缓存入口，并把文件上传进度放到这个缓存里。这个入口的值取决于POST变量APC_UPLOAD_PROGRESS的值。

如果你仔细看他的例子代码，你发现他用了apc_fetch来读内存值。同时在共享内存里，包含了APC_UPLOAD_PROGRESS这个魔术数字。

但是怎么让APC像这样工作呢？文档中并没有告诉我们。其实在CVS里的安装说明上写了：
在php.ini文件设置apc.rfc1867=1就行了。

我把例子代码弄过来了:

if($_SERVER['REQUEST_METHOD']=='POST') {
$status = apc_fetch('upload_'.$_POST['APC_UPLOAD_PROGRESS']);
$status['done']=1;
echo json_encode($status);
exit;
} else if(isset($_GET['progress_key'])) {
$status = apc_fetch('upload_'.$_GET['progress_key']);
echo json_encode($status);
exit;
}
<script type="text/javascript" src="/yui/yahoo.js"></script>
<script type="text/javascript" src="/yui/event.js"></script>
<script type="text/javascript" src="/yui/dom.js"></script>
<script type="text/javascript" src="/yui/animation.js"></script>
<script type="text/javascript" src="/yui/dragdrop.js"></script>
<script type="text/javascript" src="/yui/connection.js"></script>
<script type="text/javascript" src="/yui/container.js"></script>
<link rel="stylesheet" type="text/css" href="/yui/build/container/assets/container.css" /><script type="text/javascript">
var fN = function callBack(o) {
var resp = eval('(' + o.responseText + ')');
var rate = parseInt(resp['rate']/1024);
if(resp['cancel_upload']) {
txt="Cancelled after "+resp['current']+" bytes!";
} else {
txt=resp['total']+" bytes uploaded!";
} txt += " Upload rate was "+rate+" kbps.";
document.getElementById('pbar').style.width = '100%';
document.getElementById('ppct').innerHTML = "100%"; document.getElementById('ptxt').innerHTML = txt;
setTimeout("progress_win.hide(); window.location.reload(true);",2000);
}
var callback = { upload:fN }
var fP = function callBack(o) { var resp = eval('(' + o.responseText + ')'); if(!resp['done']) { if(resp['total']) { var pct = parseInt(100*(resp['current']/resp['total'])); document.getElementById('pbar').style.width = ''+pct+'%'; document.getElementById('ppct').innerHTML = " "+pct+"%"; document.getElementById('ptxt').innerHTML = resp['current']+" of "+resp['total']+" bytes"; } setTimeout("update_progress()",500); } else if(resp['cancel_upload']) { txt="Cancelled after "+resp['current']+" bytes!"; document.getElementById('ptxt').innerHTML = txt; setTimeout("progress_win.hide(); window.location.reload(true);",2000); } } var progress_callback = { success:fP }
function update_progress() { progress_key = document.getElementById('progress_key').value; YAHOO.util.Connect.asyncRequest('GET','progress.php?progress_key='+progress_key, progress_callback); }
var progress_win;
function postForm(target,formName) {
YAHOO.util.Connect.setForm(formName,true);
YAHOO.util.Connect.asyncRequest('POST',target,callback); /* Is there some event that triggers on an aborted file upload? */ /* YAHOO.util.Event.addListener(window, "abort", function () { alert('abort') } ); */ progress_win = new YAHOO.widget.Panel("progress_win", { width:"421px", fixedcenter:false, underlay:"shadow", close:false, draggable:true, modal:true, effect:{effect:YAHOO.widget.ContainerEffect.FADE, duration:0.3} } ); progress_win.setHeader("Uploading "+document.getElementById('test_file').value+" ..."); progress_win.setBody('
<div style="height: 1em; width: 400px; border:1px solid #000;">
<div id="pbar" style="background: #99e; height: 98%; width:0%; float:left;"> </div>
<div id="ppct" style="height: 90%; position: absolute; margin: 1 0 0 185;">0%</div>
</div>
<div id="ptxt" style="margin: 3 0 0 5">0 of 0 bytes</div>
'); progress_win.render(document.body); update_progress(); }</script>
<form method="post" onsubmit="postForm('progress.php','upload_form'); return false;" id="upload_form"><input name="APC_UPLOAD_PROGRESS" type="hidden" id="progress_key" /><input name="test_file" type="file" id="test_file" />
<input type="submit" /> </form>
<p id="progress_win"> </p>
?>

附本人意见：
php5.2之前解决大文件上传进度条显示一种是猜临时文件名另一种是用php创建webserver,需要iptables打开一些80之外的端口，还有一些是自己编译apache或php模块，基本没太大用途。有时间我详细说一下这几种情况。
目前这个看起来似乎是一个比较漂亮的解决办法。但是仍需要系统管理员(root)权限来装APC和改php.ini文件。
希望在更新版本中php能给出一个比较好的解决文件上传的办法。