PHP：将多个数组键的地址链接到另一个更大的数组中

Question

I want to combine 3 small arrays that have unique keys between them into 1 big array but when I modify a value in the big array I want it also to reflect in the corresponding small array.

For example I have these 3 small arrays:

$arr1 = ['key1' => 'data1', 'key2' => 'data2'];
$arr2 = ['key3' => 'data3', 'key4' => 'data4', 'key5' => 'data5'];
$arr3 = ['key6' => 'data6'];

I want to have a $bigArray that has each key's address linked/mapped to each value of the small arrays. So if I do something like:

$bigArray['key4'] = 'something else';

then it would modify $arr2['key4'] to the same value ('something else').

If I try something like:

$bigArray = [&$arr1, &$arr2, &$arr3];

It has the unfortunate effect of making a multidimensional array with the keys to the values mapped.

Answer 1

Two ways i found

<?php
error_reporting(E_ALL);

$arr1 = ['key1' => 'data1', 'key2' => 'data2'];
$arr2 = ['key3' => 'data3', 'key4' => 'data4', 'key5' => 'data5'];
$arr3 = ['key6' => 'data6'];

$big = [];
if (true) {
    foreach (['arr1', 'arr2', 'arr3'] as $v) {
        foreach (array_keys($$v) as $k) {
            $big[$k] = &${$v}[$k];
        }
    }
}
else {
    foreach ([&$arr1, &$arr2, &$arr3] as &$v) {
        foreach (array_keys($v) as $k) {
            $big[$k] = &$v[$k];
        }
    }
}


$big['key1'] = 'data1mod';
print_r($big);
print_r($arr1);

3rd way with function

$big = [];
$bindToBig = function (&$a) use (&$big) {
    foreach (array_keys($a) as $k) {
        $big[$k] = &$a[$k];
    }
};

$bindToBig($arr1);
$bindToBig($arr2);
$bindToBig($arr3);