$re = '/(?:([a-z]+)(?::\/\/))?((?:www.)?(?:\w+-?)+\w+(?:\.\w{2,3}){1,2})\/((?:(?:\w+-?\w+\/?)+)\.\w+)(?:(?:\?)([^#]*)(?:(?:#)(\w+))?)?/i';
$str = 'http://domain.com/path/index.html?key=value#hash';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php