Use an array as an index to access a multidimensional array in PHP

Question

I am having a problem accessing an object in a multidimensional array.

THE CONTEXT

Basically, I have an object (category) which consists of Name, ID, ParentID and more. I also have an array ultimateArray which is multidimentional.

For a given category, I am writing a function (getPath()) that will return an array of ids. For example, an object named Granny Smith has a parentID of 406 and is therefore a child of Food(5) -> Fruits(101) -> Apples(406). The function will return either an array or string of the ids of the objects parents. In the above example this would be: 5 -> 101 -> 406 or ["5"]["101"]["406"] or [5][101][406]. Food is a root category!

THE PROBLEM

What I need to do is use whatever is returned from getPath() to access the category id 406 (Apples) so that I can add the object Granny Smith to the children of Apples.

The function $path = $this->getPath('406'); is adaptable. I am just having difficulty using what is returned in the following line:

$this->ultimate[$path]['Children'][]= $category;

It works when I hard code in:

$this->ultimate["5"]["101"]["406"]['Children'][]= $category;
//or
$this->ultimate[5][101][406]['Children'][]= $category;

Any help is much appreciated.

Answer 1

Suppose you have the array like below

<?php
$a = array(
        12 => array(
                65 => array(
                    90 => array(
                        'Children' => array()
                    )
                )
            )
    );

$param = array(12, 65, 90); // your function should return values like this
$x =& $a; //we referencing / aliasing variable a to x
foreach($param as $p){
    $x =& $x[$p]; //we step by step going into it
}
$x['Children'] = 'asdasdasdasdas';
print_r($a);

?>`

You can try referencing or aliasing it
http://www.php.net/manual/en/language.references.whatdo.php
The idea is to make a variable which is an alias of your array and going deep from the variable since we can't directly assigning multidimensional key from string (AFAIK)

output

Array
(
    [12] => Array
        (
            [65] => Array
                (
                    [90] => Array
                        (
                            [Children] => asdasdasdasdas
                        )

                )

        )

)