Is it possible to assign keys to array elements in PHP from a value column with less code?

Question

Let's assume I have an array of elements, which are arrays themselves, like so:

$array = [
    ['foo' => 'ABC', 'bar' => 'DEF'],
    ['foo' => 'ABB', 'bar' => 'DDD'],
    ['foo' => 'BAC', 'bar' => 'EFF'],
];

To set the values of the foo field as the key of the array I could do this:

foreach ($array as $element) {
    $new_array[$element['foo']] = $element;
}
$array = $new_array;

The code is naturally trivial, but I've been wondering whether there's an in-built that can do the same for me.

[`array_column`](http://php.net/array_column) + [`_combine`](http://php.net/array_combine) — mario, May 13 '19 at 08:06
No need the `array_combine` it is build in the `array_column` — dWinder, May 13 '19 at 08:14

score 8 · Accepted Answer · edited Feb 01 '21 at 10:29

8

Notice array_column can get index as well (third argument):

mixed $index_key = NULL

So just use as:

array_column($array, null, 'foo');

edited Feb 01 '21 at 10:29

RiggsFolly

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answered May 13 '19 at 08:11

dWinder

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score 3 · Answer 2 · answered May 13 '19 at 08:07

Here is one liner for your case,

$temp = array_combine(array_column($array, 'foo'), $array);

Working demo.

array_combine — Creates an array by using one array for keys and another for its values
array_column — Return the values from a single column in the input array

score 0 · Answer 3 · answered May 13 '19 at 08:14

0

You can also do it with array_reduce

$new_array = array_reduce($array, function($carry, $item) {
    $carry[$item['foo']] = $item;
    return $carry;
}, []);

answered May 13 '19 at 08:14

jakub wrona

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Is it possible to assign keys to array elements in PHP from a value column with less code?

3 Answers3