PHP Regex validate letters and Spanish accent -

how can add/improvised code spanish accent considered valid in addition normal alphabet (a-z)

i have following in code

public static function isalpha($s){   $reg = "#[^a-z\s-]#i";   $count = preg_match($reg, $s, $matches);   return $count == 0; } 

as found in answer this question, match accented characters using full letter unicode property \p{l}. includes regular a-z characters along accented ones, replace a-z in expression so:

$reg = "#[^\p{l}\s-]#u"; 

note use need utf-8 modifier u after closing delimiter, docs such unicode "character types available when utf-8 mode selected".