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'];