传统的处理文件下载隐藏真实地址，相信很多小伙伴都能够在网上找到以下代码：

header('Content-Description: File Transfer');
 
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($filepath));
header('Content-Transfer-Encoding: binary');
header('Expires: 0′);
header('Cache-Control: must-revalidate, post-check=0, pre-check=0′);
header('Pragma: public');
header('Content-Length: ' . filesize($filepath));
readfile($file_path);

代码确实能下载文件，但是，当文件过大的时候，就会出现意想不到的错误:

• 下载的文件莫名变小
• 下载的文件网络错误

以下为大文件正常下载代码：

$filesize=filesize($file)+1000;
 header('Content-Description:File Transfer');
 header("Content-Type:application/octet-stream");
 header('Content-Transfer-Encoding:binary');
 header("Accept-Ranges: bytes");
 header('Expires:0');
 header('Cache-Control:must-revalidate');
 header('Pragma:public');
 header("Content-Length:".$filesize);
 header("Content-Disposition:attachment;filename=".$file_naked);
$fp = fopen($file, "rb"); 
fseek($fp,0); 
while (!feof($fp)) { 
    set_time_limit(0); 
    print (fread($fp, 1024 * 8)); 
    flush(); 
    ob_flush(); 
} 
fclose($fp); 
exit ();