PHP: Modifying array recursively? - php

Question

I have tried to make a function that iterates through the following array to flatten it and add parent id to children, where applicable. I just can't make it work, so I hope that anyone here has an idea of what to do:
Here's the starting point:
Array
(
[0] => Array (
[id] => 1
[children] => array (
[id] => 2
[children] => Array (
[0] => Array (
[id] => 3
)
)
)
)
The expected result :
Array (
[0] => array (
[id] => 1
)
[1] => array (
[id] => 2
)
[2] => array (
[id] => 3,
[parent] => 2
)
)
Hope that anyone can point me in the right direction. Thanks a lot!
Solution (Thanks to Oli!):
$output = array();
function dejigg($in) {
global $output;
if (!isset($in['children'])) {
$in['children'] = array();
}
$kids = $in['children'] or array();
unset($in['children']);
if (!isset($in['parent'])) {
$in['parent'] = 0; // Not neccessary but makes the top node's parent 0.
}
$output[] = $in;
foreach ($kids as $child) {
$child['parent'] = $in['id'];
dejigg($child); // recurse
}
return $output;
}
foreach ($array as $parent) {
$output[] = dejigg($parent);
}
$array = $output;
print("<pre>".print_r($array,true)."</pre>");

Answer 1

I've tested it this time. This does work!
$input = array( array('id' => 1, 'children'=>array( array('id'=>2, 'children'=>array( array('id'=>3) ) ) ) ) );
$output = [];
function dejigg($in) {
global $output;
$kids = $in['children'] or array();
unset($in['children']);
$output[] = $in;
foreach ($kids as $child) {
$child['parent'] = $in['id'];
dejigg($child); // recurse
}
}
foreach ($input as $parent)
dejigg($parent);
print_r($output);
And it returns:
Array
(
[0] => Array
(
[id] => 1
)
[1] => Array
(
[id] => 2
[parent] => 1
)
[2] => Array
(
[id] => 3
[parent] => 2
)
)