文件上传是WEB应用必备功能，尤其是在处理大文件上传的时候，十分需要上传时候实时显示上传进度。PHP实现上传进度条比较麻烦，一种是PHP创始人写的那个APC扩展，另外一种则需要使用PECL扩展模块uploadprogress实现。但是他们各有不足：
1、他们都需要额外安装(我们并没有打算把APC加入PHP5.2.6中)；
2、它们都使用本地机制来存储这些信息, APC使用共享内存, 而uploadprogress使用文件系统(不考虑NFS), 这在多台前端机的时候会造成麻烦。
鉴于此，本文介绍一个最方便，也最简单的实现上传进度条的方法：使用swfload实现PHP上传进度条。可以实现多文件一起上传哦。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>SWFUpload上传例子- SWFObject上传例子</title>
<link href="../css/default.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="../swfupload/swfupload.js"></script>
<script type="text/javascript" src="js/swfupload.swfobject.js"></script>
<script type="text/javascript" src="js/swfupload.queue.js"></script>
<script type="text/javascript" src="js/fileprogress.js"></script>
<script type="text/javascript" src="js/handlers.js"></script>
<script type="text/javascript">
var swfu;
SWFUpload.onload = function () {
var settings = {
flash_url : "../swfupload/swfupload.swf",
upload_url: "upload.php",
post_params: {
"PHPSESSID" : "NONE",
"HELLO-WORLD" : "Here I Am",
".what" : "OKAY"
},
file_size_limit : "100 MB",//文件大小限制
//file_types : "*.jpg;*.gif;*.png;*.jpeg;*.flv;*.mp4;*.avi;*wmv",
file_types : "*.*",
file_types_description : "All Files",//文件类型
file_upload_limit : 100,
file_queue_limit : 0,
custom_settings : {
progressTarget : "fsUploadProgress",
cancelButtonId : "btnCancel"
},
debug: false,
// Button Settings
//button_image_url : "XPButtonUploadText_61x22.png",
button_image_url: "TestImageNoText_65x29.png",//按钮图片
button_placeholder_id : "spanButtonPlaceholder",//按钮id
button_text: '<span class="theFont">浏览</span>',//按钮文字
button_text_style: ".theFont { font-size: 16; }",//按钮文字字号
button_text_left_padding: 12,//按钮左边距
button_text_top_padding: 3,//按钮上边距
button_width: "65",//按钮宽
button_height: "29",//按钮高
//button_width: 61,
//button_height: 22,
// The event handler functions are defined in handlers.js
swfupload_loaded_handler : swfUploadLoaded,
file_queued_handler : fileQueued,
file_queue_error_handler : fileQueueError,
file_dialog_complete_handler : fileDialogComplete,
upload_start_handler : uploadStart,
upload_progress_handler : uploadProgress,
upload_error_handler : uploadError,
upload_success_handler : uploadSuccess,
upload_complete_handler : uploadComplete,
queue_complete_handler : queueComplete, // Queue plugin event
// SWFObject settings
minimum_flash_version : "9.0.28",
swfupload_pre_load_handler : swfUploadPreLoad,
swfupload_load_failed_handler : swfUploadLoadFailed
};
swfu = new SWFUpload(settings);
}
</script>
</head>
<body>
<div id="content">
<h2>SWFObject上传例子</h2>
<form id="form1" action="index.php" method="post" enctype="multipart/form-data">
<p>点击“浏览”按钮，选择您要上传的文档文件后，系统将自动上传并在完成后提示您。</p>
<div id="divSWFUploadUI">
<div class="fieldset flash" id="fsUploadProgress"><span class="legend">快速上传</span></div>
<p id="divStatus">0 个文件已上传</p>
<p>
<span id="spanButtonPlaceholder"></span>
<input id="btnCancel" type="button" value="取消所有上传" disabled="disabled" style="margin-left: 2px; height: 29px; font-size: 8pt;" />
<br />
</p>
</div>
<noscript>
<div style="background-color: #FFFF66; border-top: solid 4px #FF9966; border-bottom: solid 4px #FF9966; margin: 10px 25px; padding: 10px 15px;">
对不起，您的浏览器不支持javascript。
</div>
</noscript>
<div id="divLoadingContent" class="content" style="background-color: #FFFF66; border-top: solid 4px #FF9966; border-bottom: solid 4px #FF9966; margin: 10px 25px; padding: 10px 15px; display: none;">
SWFUpload上传组件正在载入，请稍后
</div>
<div id="divLongLoading" class="content" style="background-color: #FFFF66; border-top: solid 4px #FF9966; border-bottom: solid 4px #FF9966; margin: 10px 25px; padding: 10px 15px; display: none;">
SWFUpload上传组件载入超时。 请确保Flash插件安装正确，并且版本支持本上传组件。
</div>
<div id="divAlternateContent" class="content" style="background-color: #FFFF66; border-top: solid 4px #FF9966; border-bottom: solid 4px #FF9966; margin: 10px 25px; padding: 10px 15px; display: none;">
SWFUpload不能载入. 请安装或升级Flash Player.
点击这里 <a href="http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash">Adobe website</a> 获得Flash Player.
</div>
</form>
</div>
</body>
</html>
upload.php部分：
if (isset($_FILES["Filedata"]) || !is_uploaded_file($_FILES["Filedata"]["tmp_name"]) || $_FILES["Filedata"]["error"] != 0) {
$upload_file = $_FILES['Filedata'];
$file_info = pathinfo($upload_file['name']);
$file_type = $file_info['extension'];
$save = 'upload/' . md5(uniqid($_FILES["Filedata"]['name'])) . '.' . $file_info['extension'];
$name = $_FILES['Filedata']['tmp_name'];
if (!move_uploaded_file($name, $save)) {
exit;
}
//将数组的输出存起来以供查看
$fileName = 'test.txt';
$postData = var_export($file_info, true);
$file = fopen('' . $fileName, "w");
fwrite($file,$postData);
fclose($file);
}
demo实例下载：点击我
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