$re = '/^(?![^\'\-_\n]*[\'\-_][^\'\-_\n]*[\'\-_])[a-z .\',-_]+$/mi';
$str = 'It should be valid if a Surname is:
abcd
abcd\'efg
abcd-efg
abcd, .efg
etc...
I also need to test if symbols do not repeat... so for example:
abcd\'\'efg
abcd-\',
Are invalid but the one:
abcd, .efg
Can be valid.
At the moment I just created this:
^[a-z .\',-_]+$
And now I\'m trying to check for all the double symbols but I cannot go ahead successfully.
Mc\'Millan, .jr';
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