$re = '/^((\+7|7|8)((\-\([0-9]{3}\)\-)|(\([0-9]{3}\))|(\s[0-9]{3}\s)|(\-[0-9]{3}\-)|[0-9]{3})[0-9]{3}((\s|\-)?)[0-9]{2}((\s|\-)?)([0-9]{2}))$/';
$str = '';
preg_match($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