Recursive traversal of object - php

Question

I'm having trouble writing a recursive function to traverse this hierarchical structure
object(stdClass)#290 (6) {
["category_id"]=>
int(1)
["parent_id"]=>
int(0)
["name"]=>
string(4) "Root"
["position"]=>
int(0)
["level"]=>
int(0)
["children"]=>
array(2) {
[0]=>
object(stdClass)#571 (7) {
["category_id"]=>
int(2)
["parent_id"]=>
int(1)
["name"]=>
string(18) "Root MySite.com"
["is_active"]=>
int(0)
["position"]=>
int(0)
["level"]=>
int(1)
["children"]=>
array(11) {
[0]=>
object(stdClass)#570 (7) {
["category_id"]=>
int(15)
["parent_id"]=>
int(2)
["name"]=>
string(9) "Widgets"
["is_active"]=>
int(1)
["position"]=>
int(68)
["level"]=>
int(2)
["children"]=>
array(19) {
[0]=>
object(stdClass)#566 (7) {
["category_id"]=>
int(24)
["parent_id"]=>
int(15)
["name"]=>
string(16) "Blue widgets"
["is_active"]=>
int(1)
["position"]=>
int(68)
["level"]=>
int(3)
["children"]=>
array(0) {
}
}
<snip....>
As you can see this nested set can go on forever.. .
What I want to return is something like this
$categories("Root" => array("Root MySite.com" => array("Widgets" => array("Blue Widgets",...))))
[EDIT] : pasting my starting point for my recursive function that will simply "flatten out" an arry or object. I would think i could modify this to make get the data structure I'm looking for but haven't been able to get it quite right.
function array_flatten($array, $return)
{
// `foreach` can also iterate through object properties like this
foreach($array as $key => $value)
{
if(is_object($value))
{
// cast objects as an array
$value = (array) $value;
}
if(is_array($value))
{
$return = array_flatten($value,$return);
}
else
{
if($value)
{
$return[] = $value;
}
}
}
return $return;
}
The question is I can't quite figure out to build the structure I'm looking for recursively, or maybe there is a more elegant php way to do this?

Answer 1

Try this
function run($o) {
$return = array();
foreach ($o->children as $child) {
$return[$child->name] = run($child);
}
return empty($return) ? null : $return;
}

Answer 2

I don't have time to write a working answer, but here's some pseudo code to do it (half PHP, half JS)
This would create a flattened version of the tree by removing the children property of each element in your list.
$flattened = array();
function addElement(&$flattened, $list) {
for ($element in $list) {
$children = $element->children;
delete $element->children;
$flattened[] = $element;
if ($children) {
addElements($flattened, $children)
}
}
}
addElements($flattened, $treeHierarchy);

Answer 3

deep_order object or assoc_array
namespace a_nsp
class object_utils{
static function deep_order($IN, $desc = NULL) { // object or assoc_array
$O = new \stdClass;
$I = (array) $IN;
$keys = array_keys($I);
$desc ? rsort($keys) : asort($keys);
foreach ($keys as $k) {
$v = $I[$k];
//$v = json_decode($I[$k],1) ?: $I[$k]; // force conversion of json_string
if (is_array($v) || is_object($v)) {
$O->$k = self::deep_order($v, $desc);
}
else {
$O->$k=$v;
}
}
return $O; // object
}
}
use like
$ordered_obj = \a_nsp\object_utils::deep_order($orig_obj)