Update multidimensional array value depending on other sibling value - php

Question

I have array this can be up to n element.
(
[children] => Array
(
[0] => Array
(
[id] => nhbs0123620cf897
[title] => Introduction
[children] => Array
(
[0] => Array
(
[id] => bylff0a76617c8
[title] => Courent3
[children] => Array
(
)
)
[1] => Array
(
[id] => xavs26efa2f51eb
[title] => Chapter
[children] => Array
(
)
)
[2] => Array
(
[id] => iezkd241d9d90
[title] => external
[children] => Array
(
)
)
[3] => Array
(
[id] => gmzh439c4f50
[title] => audio
[children] => Array
(
)
)
[4] => Array
(
[id] => niugd4e18b0
[title] => url
[children] => Array
(
)
)
[5] => Array
(
[id] => unpgdb1b7694
[title] => new
[children] => Array
(
)
)
[6] => Array
(
[id] => ssvc2025c0c8a
[title] => simple
[children] => Array
(
[0] => Array
(
[id] => ssvc2025c0c
[title] => later
[children] => Array
(
)
)
)
)
)
)
[1] => Array
(
[id] => rwtae5d9482
[title] => Summary
[children] => Array
(
[0] => Array
(
[id] => ssvc2025c0
[title] => later
[children] => Array
(
)
)
)
)
[2] => Array
(
[id] => rwtae5d9482709
[title] => Course
[children] => Array
(
)
)
)
)
Here I want to update title value depending on id for each element in array.
What i have tried
1 used array_walk_recursive here i can update data but while updating not able to check id value .
array_walk_recursive(array, function(&$value, $key) {
// not able to check if id == 'something' .this is what i need
if ($key == 'title') {
$value = 'updated data';
}
});
Second tried in for each loop but not able to hold array index to get actual array
function myfun($array,&$out){
foreach($array['children'] as $key=>$val){
if(!empty($val['children'])){
$out['children'][$key]['title'] = $val['title']; // this is not right key
$this->myfun($val,$out['children']);
}else{
$out['children'][$key]['title'] = $val['title']; // this is not right key
}
}
}
here also not able to return array in $out array.
Only thing i have that children key using this if any function can be written.
I am hoping this should be possible in php array functions.

Answer 1

You are close - all you need is to use the & - this will send the array as reference so any change on him will be on the original array. Can look in PHP manual for more knowledge.
Consider the following:
$arr = [["id" => 1, "title" => "aaa", "children" => []], ["id" => 2, "title" => "bbb", "children" => [["id" => 3, "title" => "ccc", "children" => []]]]];
function modifyTitle(&$arr, $id, $newVal) {
foreach($arr as &$e) {
if ($e["id"] == $id)
$e["title"] = $newVal;
modifyTitle($e["children"], $id, $newVal);
}
}
modifyTitle($arr, 3, "zzz");
print_r($arr); // now the original array children changed
Live example: https://3v4l.org/ZbiB9