或者用到的php代码

<?php

/**
*
* delay.php?f=file.js&t=100
*
* 延时100毫秒加载file.js
*
* */

//得到扩展名
function get_extend($file_name) {
$extend =explode("." , $file_name);
$va=count($extend)-1;
return $extend[$va];
}
 
/**
* begin
*/
//cdn上存在的各种可能的文件类型
$header = array(
    'js' => 'Content-Type: application/x-javascript',
    'css' => 'Content-Type: text/css',
    'jpg' => 'Content-Type: image/jpg',
    'gif' => 'Content-Type: image/gif',
    'png' => 'Content-Type: image/png',
    'jpeg' => 'Content-Type: image/jpeg',
    'swf' => 'Content-Type: application/x-shockwave-flash'
);


$filename = $_GET['f'];
$R_files = file($_GET['f']);

if(empty($type)) {
$type = get_extend($filename);
}

header($header[$type]);

ob_flush();
flush();
sleep($_GET['t']);

//var_dump($R_files);

echo join("\n",$R_files);

?>

http://cdn/你的目录/delay.php?f=yourfile.js&t=100

ob_flush();
flush();
sleep($_GET['t']);