php获取远程文件大小的三种方法

php获取远程文件大小的三种方法

1、使用file_get_contents()

<?php

$file = file_get_contents($url);

echo strlen($file);

?>

2. 使用get_headers()

<?php

$header_array = get_headers($url, true);

$size = $header_array['Content-Length'];

echo $size;

//by www.jbxue.com

?>

说明：

需要打开allow_url_fopen!
如未打开会显示
Warning: get_headers() [function.get-headers]: URL file-access is disabled in the server configuration
3.使用fsockopen()

<?php

 function get_file_size($url) {

     $url = parse_url($url);



     if (empty($url['host'])) {

         return false;

     } //by www.jbxue.com



     $url['port'] = empty($url['post']) ? 80 : $url['post'];

     $url['path'] = empty($url['path']) ? '/' : $url['path'];



     $fp = fsockopen($url['host'], $url['port'], $error);



     if($fp) {

         fputs($fp, "GET " . $url['path'] . " HTTP/1.1\r\n");

         fputs($fp, "Host:" . $url['host']. "\r\n\r\n");



         while (!feof($fp)) {

             $str = fgets($fp);

             if (trim($str) == '') {

                 break;

             }elseif(preg_match('/Content-Length:(.*)/si', $str, $arr)) {

                 return trim($arr[1]);

             }

         }

         fclose ( $fp);

         return false;

     }else {

         return false;

     }

 }

 ?>