Recursive search and remove in array?

问题

I am working with a multidimensional array I want to be able to remove an array (and all children) which match an id.

The function I have tried is:

function removeKey($key, $array, $childKey = 'children'){
    if(isset($array[$key])){
        unset($array[$key]);
        return $array;
    }

    foreach($array as &$item)
        if(isset($item[$childKey]))
            $item = removeKey($key, $item[$childKey], $childKey);

    return $array;
}

My example array is:

Array
(
    [5] => Array
        (
            [id] => 5
            [parent_id] => 
            [menu_title] => Drinks
            [page_title] => Drinks
            [status] => 1
            [products] => 0
        )

    [1] => Array
        (
            [id] => 1
            [parent_id] => 
            [menu_title] => Electronics
            [page_title] => Electronics
            [status] => 1
            [products] => 0
            [children] => Array
                (
                    [2] => Array
                        (
                            [id] => 2
                            [parent_id] => 1
                            [menu_title] => Computers
                            [page_title] => Computers
                            [status] => 1
                            [products] => 0
                            [children] => Array
                                (
                                    [4] => Array
                                        (
                                            [id] => 4
                                            [parent_id] => 2
                                            [menu_title] => Apple
                                            [page_title] => Apple - Imacs and Macbooks
                                            [status] => 1
                                            [products] => 0
                                        )

                                )

                        )

                    [3] => Array
                        (
                            [id] => 3
                            [parent_id] => 1
                            [menu_title] => Mobile Phones
                            [page_title] => Mobile Phones
                            [status] => 1
                            [products] => 0
                        )

                )

        )

)

and the result I am looking for (calling the function with (2, $array, 'children')) is:

Array
(
    [5] => Array
        (
            [id] => 5
            [parent_id] => 
            [menu_title] => Drinks
            [page_title] => Drinks
            [status] => 1
            [products] => 0
        )

    [1] => Array
        (
            [id] => 1
            [parent_id] => 
            [menu_title] => Electronics
            [page_title] => Electronics
            [status] => 1
            [products] => 0
            [children] => Array
                (

                    [3] => Array
                        (
                            [id] => 3
                            [parent_id] => 1
                            [menu_title] => Mobile Phones
                            [page_title] => Mobile Phones
                            [status] => 1
                            [products] => 0
                        )

                )

        )

)

but the result I am getting is

Array
(
    [5] => Array
        (
            [id] => 5
            [parent_id] => 
            [menu_title] => Drinks
            [page_title] => Drinks
            [status] => 1
            [products] => 0
        )

    [1] => Array
        (
            [3] => Array
                (
                    [id] => 3
                    [parent_id] => 1
                    [menu_title] => Mobile Phones
                    [page_title] => Mobile Phones
                    [status] => 1
                    [products] => 0
                )

        )

)

I have no idea what's going on here!

回答1:

You can ease things by only using references.

function removeKey($key, &$array, $childKey = 'children'){
    if(isset($array[$key])){
        unset($array[$key]);
        return;
    }

    foreach($array as &$item)
        if(isset($item[$childKey]))
            removeKey($key, $item[$childKey], $childKey);
}

Example:

$arr = array(...);
removeKey('key', $arr, $chilKey);
// Just continue using $arr

回答2:

What about multidimensional array? I was researched for a couple of hours for this solution, nowhere found an optimal solution. so, i wrote it by myself

function allow_keys($arr, $keys)
    {
        $saved = [];

        foreach ($keys as $key => $value) {
            if (is_int($key) || is_int($value)) {
                $keysKey = $value;
            } else {
                $keysKey = $key;
            }
            if (isset($arr[$keysKey])) {

                $saved[$keysKey] = $arr[$keysKey];
                if (is_array($value)) {

                    $saved[$keysKey] = allow_keys($saved[$keysKey], $keys[$keysKey]);
                }
            }
        }
        return $saved;
    }

use: example

$array = [
        'key1' => 'kw',
        'loaa'=> ['looo'],
        'k'    => [
            'prope' => [
                'prop'  => ['proo', 'prot', 'loolooo', 'de'],
                'prop2' => ['hun' => 'lu'],
            ],
            'prop1' => [

            ],
        ],
    ];

call: example

allow_keys($array, ['key1', 'k' => ['prope' => ['prop' => [0, 1], 'prop2']]])

output:

Array ( [key1] => kw [k] => Array ( [prope] => Array ( [prop] => Array ( [0] => proo [1] => prot ) [prop2] => Array ( [hun] => lu ) ) ) ) 

so you get only needed keys from the multidimensional array. it is not limited only for "multidimensional", you can use it by passing an array like

['key1', 'loaa']

output you get:

Array ( [key1] => kw [loaa] => Array ( [0] => looo ) )

hope someone helps this one, as i searched a lot, and nothing found. cheers!

来源：https://stackoverflow.com/questions/12053433/recursive-search-and-remove-in-array