从一个标准 url 里取出文件的扩展名

$url = 'http://www.sina.com.cn/abc/de/fg.php?id=1';

 

//解析URL,得到一数组

$p_url = parse_url($url);

/*Array ( [scheme] => http [host] => www.sina.com.cn [path] => /abc/de/fg.php [query] => id=1 )*/ 然后 $path_info = pathinfo($p_url['path']); 得到一数组 /*Array ( [dirname] => /abc/de [basename] => fg.php [extension] => php [filename] => fg )*/ echo $path_info['extension'];