php make nested array from multiple arrays - php

Question

I want to make a nicely structured category with parent tree, but i can't seem to find the right way to get do this properly.
This is the premis:
1 product has many categories.
1 category may have a parent.
this is the array I currently have (the values in these arrays are just an example)
array:4[
1=> array:2 [
2 =>2
4 => 4
]
2=> array:1[
3=>3
]
3=> array:1[
5=>5
]
9=> array:1[
6=>6
]
]
now i want this
array:4[
1=> array:2 [
2 => array:1 [
3=> array:1 [
5=>5
]
]
4 => 4
]
9=> array:1[
6=>6
]
]
how do I convert the first to the second while keeping the array keys, I want to use the keys to call upon an another array with all the relevant objects and data
so i can get this as a result:
http://www.bootply.com/dFeKoQmgb2

Answer 1

What if you try the following code. Note that there must be a better approach without changing the source array inside recursion.
$array = array(
1 => array(
2 => 2,
4 => 4
),
2 => array(
3 => 3
),
3 => array(
5 => 5
),
9 => array(
6 => 6
)
);
//we need the copy to delete there nodes that have been re-atached. Otherwise, we end up changing the array itself within recursion, which is not good
$arrayCopy = $array;
function recursive(&$array, &$arrayCopy) {
foreach($array as $key => &$value) {
//if we found the leaf node
if(!is_array($value)) {
// and there is something in the array copy with this index
if(array_key_exists($key, $arrayCopy)) {
// re-attach it to the initial array. $value is passed by reference. BTW, not a good approach as I stated above, but it works on the sample data
$value = $arrayCopy[$key];
// remove that node from array copy in order to not double process it.
unset($arrayCopy[$key]);
// call it again for the leaf-node value
recursive($value, $arrayCopy);
}
// here is recursion exit, if we don't find anything in the arracy copy for the fiven leaf node
} else {
//recursive call it for the node
recursive($value, $arrayCopy);
}
}
}
// launch the recursion
recursive($array, $arrayCopy);
// now we need to remove the nodes that have been removed from the array copy, i.e. the ones being re-attached. We could not do this in the recursion
$result = array();
foreach(array_keys($arrayCopy) as $initial_key) {
$result[$initial_key] = $array[$initial_key];
}
var_dump($result);

Answer 2

for now I fixed it using this function, I'm sure there is a more elegant way, since it only works when the parent is also in the array, for this but it works
array (size=5)
0 =>
array (size=3)
'id' => int 2
'parent' => int 1
'name' => string 'voluptatem' (length=10)
1 =>
array (size=3)
'id' => int 3
'parent' => int 2
'name' => string 'qui' (length=3)
2 =>
array (size=3)
'id' => int 4
'parent' => int 1
'name' => string 'qui' (length=3)
3 =>
array (size=3)
'id' => int 5
'parent' => int 3
'name' => string 'voluptate' (length=9)
4 =>
array (size=3)
'id' => int 6
'parent' => int 9
'name' => string 'optio' (length=5)
private function generatePageTree($datas, $parent=0, $limit=0)
{
if ($limit > 100) return '';
$tree='<ul class="list-group">';
foreach ($datas as $data) {
if ($data['parent'] == $parent) {
$tree.='<div class="panel-group" id="accordion" role="tablist" aria-multiselectable="false">
<div class="panel panel-default">
<div class="panel-heading" role="tab" id="heading' . $data['id'] . '">
<h4 class="panel-title" style="height:50px;">
<a class="collapsed" role="button" data-toggle="collapse" data-parent="accordion" href="#collapse' . $data['id'] . '" aria-expanded="false" aria-controls="collapse' . $data['id'] . '">
' . $data['name'] . '
</a>
<i class="fa fa-search"></i>Toon
</h4>
</div>
<div id="collapse' . $data['id'] . '" class="panel-collapse collapse out" role="tabpanel" aria-labelledby="heading' . $data['id'] . '">
<div class="panel-body">';
$tree.=$this->generatePageTree($datas, $data['id'], $limit ++);
$tree.='</div>
</div>
</div>
</div>
';
}
}
$tree.='</ul>';
return $tree;
}