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<?php class RecursionImplementation { public static function recursionInitiator($array, $keylist) { self::$keys = explode(",", $keylist); if(count(self::$keys) == 0) return $array; $array = self::recursion($array); return $array; } private static function recursion($array) { $all_keys = array_keys($array); $intersection = array_intersect($all_keys, self::$keys); $difference = array_diff($all_keys, self::$keys); $number_of_intersecting_keys = count($intersection); $number_of_non_intersecting_keys = count($array) - $number_of_intersecting_keys; if($number_of_intersecting_keys + $number_of_non_intersecting_keys == 0) return; if($number_of_intersecting_keys >= 1) { foreach($intersection as $key) { unset($array[$key]); $array[$key] = self::$asterisk; } } if($number_of_non_intersecting_keys >= 1) { foreach($difference as $key) { if(is_array($array[$key])) { $value = self::recursion($array[$key]); unset($array[$key]); $array[$key] = $value; } } } return $array; } private static $keys; private static $asterisk = "**"; } $information = array("login" => "someUsername", "password" => "somePassword", "card_pin"=>"card_1234", "pin"=>"pin_356", "iin" => "iin_123", "shipping" => array("value" => array("telephone" => array("inner_value" => "telephone_998"))), "cardnumber" => "card_number_876", "customer_id" => "customer_654", "telephone" => "someOtherTelephoneNumber555"); $list = "telephone,login"; print_r($information); echo "\n\n"; $final_array = RecursionImplementation::recursionInitiator($information, $list); print_r($final_array);