- var_dump: documentation ( source)
- parse_url: documentation ( source)
<?php
$url='https://m.facebook.com/home.php?refsrc=https%3A%2F%2Fm.facebook.com%2F&refid=8&_rdr';
var_dump(
parse_url($url,PHP_URL_SCHEME),
parse_url($url,PHP_URL_HOST),
parse_url($url,PHP_URL_HOST | PHP_URL_SCHEME),
parse_url($url,-1)
);