Find all second level keys in multi-dimensional array in php

Question

I want to generate a list of the second level of keys used. Each record does not contain all of the same keys. But I need to know what all of the keys are. array_keys() doesn't work, it only returns a list of numbers.

Essentially the output Im looking for is:

action, id, validate, Base, Ebase, Ftype, Qty, Type, Label, Unit

I have a large multi-dimensional array that follows the format:

Array (     [0] => Array         (             [action] => A             [id] => 1             [validate] => yes             [Base] => Array                 (                     [id] => 2945                 )              [EBase] => Array                 (                     [id] => 398                 )              [Qty] => 1             [Type] => Array                 (                     [id] => 12027                 )              [Label] => asfhjaflksdkfhalsdfasdfasdf             [Unit] => asdfas         )      [1] => Array         (             [action] => A             [id] => 2             [validate] => yes             [Base] => Array                 (                     [id] => 1986                 )              [FType] => Array                 (                     [id] => 6                 )              [Qty] => 1             [Type] => Array                 (                     [id] => 13835                 )              [Label] => asdssdasasdf             [Unit] => asdger         ) ) 

Thanks for the help!

Answer 1

<?php  // Gets a list of all the 2nd-level keys in the array function getL2Keys($array) {     $result = array();     foreach($array as $sub) {         $result = array_merge($result, $sub);     }             return array_keys($result); }  ?> 

edit: removed superfluous array_reverse() function