How to get the array keys of arrays inside an array

Question

I have a collection that has 2 arrays like on this picture:

So there are:

array 63 has two keys 70 and 72
array 64 has key 71

What i want to do is to get the keys 70, 72, 71.

How to get those keys??

Joseph Silber · Accepted Answer · 2017-03-05 15:53:34Z

1

$keys = $collection->flatMap(function ($item) {
    return array_keys($item);
});

If you think there may be duplicates, tack on a call to unique at the end:

$keys = $collection->flatMap(function ($item) {
    return array_keys($item);
})->unique();

answered Mar 5, 2017 at 15:53

Joseph Silber

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1 Comment

That's what I call "slam & dunk"

Roman · Accepted Answer · 2017-03-05 15:45:48Z

1

Try this:

$keys = [];
$collection->each(function ($item) use (&$keys) {
    $keys = array_merge($keys, array_keys($item));
});

answered Mar 5, 2017 at 15:45

Roman

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