Children nodes moved to the root level on an hierarchy array - php

Question

I have the following array on a hierarchy structure - It's basically an array with categories and its children under the 'child' key:
Array
(
[category_id] => 1
[parent_id] => 0
[name] => Commercial
[child] => Array
(
[0] => Array
(
[category_id] => 48
[parent_id] => 1
[name] => lights
[child] => Array
(
)
)
[1] => Array
(
[category_id] => 12
[parent_id] => 1
[name] => beacons
[child] => Array
(
[0] => Array
(
[category_id] => 91
[parent_id] => 12
[name] => blue beacons
[child] => Array
(
)
)
)
)
)
)
What I am trying to do is write a recursive function to reorganize this array as an ONE LEVEL array only. Instead of having its children inside the 'child' key, I want it to be part of the array root level. Like this:
[0] => Array
(
[category_id] => 1
[parent_id] => 0
[name] => Commercial
)
[1] => Array
(
[category_id] => 48
[parent_id] => 1
[name] => lights
)
[2] => Array
(
[category_id] => 12
[parent_id] => 1
[name] => beacons
)
[3] => Array
(
[category_id] => 91
[parent_id] => 12
[name] => blue beacons
)
Any ideas?
Thanks!

Answer 1

The following recursive function should serve your purpose:
function one_level_array($arr){
$ret = array();
$ret[] = array_diff_key($arr, array("child" => ""));
if(array_key_exists("child", $arr)){
foreach($arr["child"] as $child){
$ret = array_merge($ret, one_level_array($child));
}
}
return $ret;
}
DEMO