$re = '/^\d{1,5}[-\p{L}][-\p{L}\d]{0,9}$/mu';
$str = '12345a235
123a
12345-aa1
12345a
12345-a
12-a235dkfsf
12-a235dkfsfs
123a-dssava-y
123a-dssava-1a
12345-aa1--asd-
12345-aa1--asd-s
-11
111111
aaaa
version 1 :: plain ... ^\\d{1,5}[-\\p{L}][-\\p{L}\\d]{0,9}$
version 2 :: named ... ^(?<digitsOnly>\\p{N}{1,5})(?<miscellaneous>[-\\p{L}][-\\p{L}\\p{N}]{0,9})$
';
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