Online PHP editor | refs for J8iNU

<?php // Array representing a possible record set returned from a database $records = array( array( 'id' => "bbb", 'first_name' => 'John', 'last_name' => 'Doe', ), array( 'id' => "aaa", 'first_name' => 'Sally', 'last_name' => array( 'id' => "zzz", 'first_name' => 'Sully', 'last_name' => 'Smith', ), ), array( 'id' => "yyy", 'first_name' => 'Jane', 'last_name' => 'Jones', ), array( 'id' => "xxx", 'first_name' => 'Peter', 'last_name' => 'Doe', ) ); function test_print($val, $key, &$third) { // var_export($val); // var_export($key); // var_export($third); // $third++; if($key == 'first_name'){ $third[] = $val; } else { print_r($key); } } $third = []; array_walk_recursive($records, 'test_print', $third); print_r($third);