php相对路径转化成绝对路径

提取 Gregarius中的一个函数。可以把网页中的相对路径自动转化成绝对路径。

<?
function relative_to_absolute($content, $feed_url) {
    preg_match(/(http|https|ftp):///, $feed_url, $protocol);
    $server_url = preg_replace("/(http|https|ftp|news):///", "", $feed_url);
    $server_url = preg_replace("//.*/", "", $server_url);

    if ($server_url == ) {
        return $content;
    }

    if (isset($protocol[0])) {
        $new_content = preg_replace(/href="//, href=".$protocol[0].$server_url./, $content);
        $new_content = preg_replace(/src="//, src=".$protocol[0].$server_url./, $new_content);
    } else {
        $new_content = $content;
    }
    return $new_content;
}
?>