举例子如下:

$url = "http://www.electrictoolbox.com/php-extract-domain-from-full-url/"; 
$parts = parse_url($url); 

输出:

Array 
( 
[scheme] => http 
[host] => www.electrictoolbox.com 
[path] => /php-extract-domain-from-full-url/ 
) 

又如:

<?php 
$url = 'http://username:password@hostname/path?arg=value#anchor'; 
print_r(parse_url($url)); 
echo parse_url($url, PHP_URL_PATH); 
?> 

输出:

Array 
( 
[scheme] => http 
[host] => hostname 
[user] => username 
[pass] => password 
[path] => /path 
[query] => arg=value 
[fragment] => anchor 
) 

可以看到,可以很容易分解出一个URL的各个部,那如果要拿指定的部分出来的话也很容易,如
echo parse_url($url, PHP_URL_PATH);
就是在第二个参数中,设定如下的参数:
PHP_URL_SCHEME, PHP_URL_HOST, PHP_URL_PORT, PHP_URL_USER, PHP_URL_PASS, PHP_URL_PATH, PHP_URL_QUERY or PHP_URL_FRAGMENT.

---