$re = '/^([\s+]+7|\s?8)((\s?\(?\s?)[\s-]?\s?\d(\s?\)?\s?)){10}$/m';
$str = '84951234567
+74951234567
8-495-1-234-567
8 (8122) 56-56-56
8-911-1234567
8 (911) 12 345 67
8-911 12 345 67
8 (911) - 123 - 45 - 67
+ 7 999 123 4567
8 ( 999 ) 1234567
8 999 123 4567
// выше - правильные, ниже - неправильные:
02
84951234567 позвать люсю
849512345
849512345678
8 (409) 123-123-123
7900123467
5005005001
8888-8888-88
84951a234567
8495123456a
+1 234 5678901
+8 234 5678901
7 234 5678901
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($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