解析PHP实现下载文件的两种方法

方法一：

 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);

方法二：

 $fileinfo = pathinfo($filename);
 header('content-type: application/x-'.$fileinfo['extension']);
 header('content-disposition: attachment; filename='.$fileinfo['basename']);
 header('content-length: '.filesize($filename));
 readfile($thefile);
 exit();