以下实例我们使用php curl 来获取远程文件大小，返回文件大小单位为字节：

<?php

// 获取远程文件大小函数

function remote_filesize($url, $user = “”, $pw = “”)

{

ob_start();

$ ch = curl_init($url);

curl_setopt($ch, CURLOPT_HEADER, 1);

curl_setopt($ch, CURLOPT_NOBODY, 1);

if(!empty($user) && !empty($pw))

{

$headers = array(‘Authorization: Basic ‘ . base64_encode(“$user:$pw”));

curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

}

$ok = curl_exec($ch);

curl_close($ch);

$head = ob_get_contents();

ob_end_clean();

$ regex = ‘/Content-Length:\s([0-9].+?)\s/’;

$count = preg_match($regex, $head, $matches);

return isset($matches[1]) ? $matches[1] . ” 字节” : “unknown”;

}

// 实例测试

echo remote_filesize(“”);

?>

以上实例输出结果为：

8416 字节