add new element to an N-level Multidimentional array in PHP - php

Question

I have an N-level Multidimentional array like this:
Array
(
[0] => Array
(
[id] => 7_cat
[text] => cat1
[children] => Array
(
[0] => Array
(
[id] => 9_cat
[text] => cat3
)
)
)
[1] => Array
(
[id] => 8_cat
[text] => cat2
)
[2] => Array
(
[id] => 13_cat
[text] => cat4
)
)
and i have an array of index like this:
Array
(
[0] => 0
[1] => children
[2] => 0
[3] => id
)
so i want to add a new element in first array in these depth. in this example i want to add a new element in $firstarray[0]['children'][0]['id'].
How can i do it?
thanks alot

Answer 1

Do Like this
Here $oldArray is your first array
$indexArray=Array
(
[0] => 0
[1] => children
[2] => 0
[3] => id
);
$indexForold=[];
foreach($indexArray as $indx){
$indexForold=$indexForold[$indx];
}
$oldArray[$indexForold]=$myVal;

Answer 2

The solution is, while traversing the array use reference to keep a reference to the current array element.
Here $nArr is your n-dimensional array and $indexArr is your index array.
And don't forget to replace <YOUR_VALUE> with your desired value.
So your code should be like this:
$arrLength = count($indexArr);
$tmpArr = null;
$i = 0;
for(; $i < $arrLength - 1; ++$i){
if($tmpArr == null){
$tmpArr = &$nArr[$indexArr[$i]];
}else{
$tmpArr = &$tmpArr[$indexArr[$i]];
}
}
$tmpArr[$indexArr[$i]] = <YOUR_VALUE>;
// now display the n-dimensional array
echo "<pre>";
print_r($nArr);
echo "</pre>";

Answer 3

You can try something like this...
$array = [
[
'id' => '7_cat',
'text' => 'cat1',
'children' => [
[
'id' => '9_cat',
'text' => 'cat3'
]
]
],
[
'id' => '8_cat',
'text' => 'cat2'
],
[
'id' => '13_cat',
'text' => 'cat4'
]
];
$multIndexValue = function (array $indexList, array $searchArray) {
$result = $searchArray;
foreach ($indexList as $index) {
$result = $result[$index];
}
return $result;
};
$search = [0, 'children', 0, 'id'];
$result = $multIndexValue($search, $array); // string(5) "9_cat"