PHP - create new array with only selected keys from an existing array

Question

What is the simplest way to get only selected keys and its values from an array in PHP? For example, if I have an array:

$meta = [
      "nickname" => [
        0 => "John"
      ]
      "first_name" =>  [
        0 => "John"
      ]
      "last_name" => [
        0 => "Doe"
      ]
      "description" => array:1 [
        0 => ""
      ]
      "rich_editing" => [
        0 => "true"
      ]
      "comment_shortcuts" => [
        0 => "false"
      ]
      "admin_color" => [
        0 => "fresh"
      ]
      "use_ssl" => array:1 [
        0 => "0"
      ]
      "show_admin_bar_front" => [
        0 => "true"
      ]
      "locale" => [
        0 => ""
      ]
      "wp_capabilities" => [
        0 => "a:1:{s:10:"subscriber";b:1;}"
      ]
      "wp_user_level" => [
        0 => "0"
      ]
      "dismissed_wp_pointers" => [
        0 => ""
      ]
      "department" => [
        0 => "Administrasjon"
      ]
      "region" => [
        0 => "Oslo"
      ]
      "industry" => [
        0 => "Bane"
      ]
    ]

What is the simplest way to get a new array with only selected keys like for example nickname, first_name, last_name, etc?

@Martijn question is how to get values of these keys. https://stackoverflow.com/questions/12887322/get-only-the-array-elements-with-certain-keys — unalignedmemoryaccess, Oct 20 '17 at 06:58
Its closed as duplicate do you think post reference given above has proper solution ? or its closed based on keyword like bots ? — Akshay Hegde, Jun 15 '21 at 15:36

score 40 · Accepted Answer · edited Aug 22 '22 at 18:45

40

Using array_flip() and array_intersect_key():

$cleanArray = array_intersect_key(
    $fullArray,  // the array with all keys
    array_flip(['nickname', 'first_name', 'last_name']) // keys to be extracted
);

edited Aug 22 '22 at 18:45

Code Slicer

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answered Oct 20 '17 at 07:00

Akshay Hegde

16,536
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36

[Same advice back in 2010](https://stackoverflow.com/a/4260168/2943403) – mickmackusa Aug 22 '22 at 22:43

score 2 · Answer 2 · answered Oct 20 '17 at 07:01

Try this;

$newArray = array();
$newArray['nickname'] = $meta['nickname'];
$newArray['first_name'] = $meta['first_name'];
$newArray['last_name'] = $meta['last_name'];

This is useful if number of keys are not many.

And if keys are many; then you can go for

$requiredKeys = ['nickname','first_name','last_name'];
foreach ($arr as $key => $value) {

        if(in_array($key,$requiredKeys))
                $newArray[$key] = $meta[$key];
}

PHP - create new array with only selected keys from an existing array

2 Answers2