将多维数组转换为简单数组

Question

I have an array like this

Array 
( 
    [0] => Array 
    ( 
        [id] => 1 [children] => Array 
        ( 
            [0] => Array 
            ( 
                [id] => 2 [children] => Array 
                ( 
                    [0] => Array 
                    ( 
                        [id] => 3 [children] => Array 
                        ( 
                            [0] => Array 
                            ( 
                                [id] => 4 
                            ) 
                        ) 
                    ) 
                ) 
            ) 
        ) 
    ) 
    [1] => Array ( 
        [id] => 5 
    ) 
    [2] => Array 
    ( 
        [id] => 6 
    ) 
    [3] => Array 
    ( 
        [id] => 7 
    ) 
    [4] => Array 
    ( 
        [id] => 8 
    ) 
    [5] => Array 
    ( 
        [id] => 9 
    ) 
)

this is dynamically generated array i need a function that takes this array as input and returns each id with its parent id

as according to this array id 2 is child of id 1 and id 3 is child of id 3 and id 4 is child of id 3

and final result id 1 is parent of id 2 and id 2 is parent of id 3 and id 3 is parent of id 4 and ids 5-9 have no parents so they have 0 as default value

Answer 1

Beside the fact that you didn't come up with any effort by yourself, i'll post a solution anyway in case someone isn't aware of a solution with PHP's RecursiveIteratorIterator

Sample Data:

$arrData = [
    [
        'id' => 1,
        'children' => [
            'id' => 2,
            'children' => [
                'id' => 3,
                'children' => [
                    'id' => 4
                ]
            ]
        ]
    ],
    [
        'id' => 5
    ],
    [
        'id' => 6
    ],
    [
        'id' => 7
    ],
    [
        'id' => 8
    ],
    [
        'id' => 9
    ],
];

Use of PHP's built int iterator classes

$arrDataConverted = [];

$iterator = new RecursiveIteratorIterator(new RecursiveArrayIterator($arrData));
foreach($iterator AS $key => $value)
{
    $arrParentdata = $iterator->getSubIterator($iterator->getDepth()-1);

    $arrItem = [
        'id' => $value,
        'parent' => (isset($arrParentdata['id']))  ?    $arrParentdata['id']   :   0
    ];
    $arrDataConverted[] = $arrItem;
}

print_r($arrDataConverted);