如何实现一次选择多个文件上传，而且异步上传

swfupload插件

<!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"> 
<meta http-equiv='Content-Type' content='text/html; charset=utf-8' />
  
<title>File upload </title> 
<link rel="Stylesheet" href="js/Plug-in/jquery.uploadify/uploadify.css" /> 
<script type="text/javascript" src="js/Plug-in/jquery.uploadify/jquery-1.3.2.min.js"></script> 
<script type="text/javascript" src="js/Plug-in/jquery.uploadify/swfobject.js"></script> 
<script type="text/javascript" src="js/Plug-in/jquery.uploadify/jquery.uploadify.v2.1.0.min.js"></script> 
<script type="text/javascript"> 
$(document).ready(function() { 
    $("#uploadify").uploadify({ 
        'uploader': 'js/Plug-in/jquery.uploadify/uploadify.swf', 
        'script': 'uploadify.php', 
        'cancelImg': 'js/Plug-in/jquery.uploadify/cancel.png', 
        'folder': 'uploadfile', 
        'queueID': 'fileQueue', 
        'auto': false, 
        'multi': true, 
    }); 
}); 
</script> 
</head> 
<body> 
MAX: 20M
</BR>
<input type="file" name="uploadify" id="uploadify" /> 
<a href="javascript:$('#uploadify').uploadifyUpload()">Upload</a>| <a href="javascript:$('#uploadify').uploadifyClearQueue()">cancel</a> 
<div id="fileQueue"></div> 
</body> 
</html>

#uploadify.php

<?php
if (!empty($_FILES)) {
    $tempFile = $_FILES['Filedata']['tmp_name'];
    $targetPath = $_SERVER['DOCUMENT_ROOT'] . $_REQUEST['folder'] . '/';
    $targetFile =  str_replace('//','/',$targetPath) . $_FILES['Filedata']['name'];
    $targetFile =  iconv("utf-8","gbk",$targetFile);
 
        move_uploaded_file($tempFile,$targetFile);
        echo "1";
}
?>