if array_column does not exist the below solution will work.
if(!function_exists("array_column"))
{
function array_column($array,$column_name)
{
return array_map(function($element) use($column_name){return $element[$column_name];}, $array);
}
}
array_column
(PHP 5 >= 5.5.0, PHP 7, PHP 8)
array_column — Retourne les valeurs d'une colonne d'un tableau d'entrée
Description
array_column() retourne les valeurs d'une colonne de array, identifiée par la clé
column_key. Optionnellement, vous pouvez fournir
un paramètre index_key pour indexer les valeurs
dans le tableau retourné par les valeurs de la colonne
index_key du tableau d'entrée.
Liste de paramètres
-
array -
Un tableau multidimensionnel ou un tableau d'objets à partir duquel on extrait une colonne de valeur. Si un tableau d'objets est fourni, alors les propriétés publiques peuvent être directement extraites. Pour que les propriétés protected ou private soient extraites, la classe doit implémenter les deux méthodes magiques __get() et __isset().
-
column_key -
La colonne de valeurs à retourner. Cette valeur peut être la clé entière de la colonne que vous souhaitez récupérer, ou bien le nom de la clé pour un tableau associatif ou le nom de la propriété. Il peut aussi valoir
nullpour retourner le tableau complet ou des objets (ceci peut être utile en conjonction du paramètreindex_keypour ré-indexer le tableau). -
index_key -
La colonne à utiliser comme index/clé pour le tableau retourné. Cette valeur peut être la clé entière de la colonne, ou le nom de la clé. La valeur est cast comme d'habitude pour les clés du tableau (cependant, antérieur à PHP 8.0.0, les objects qui supportent une conversion en chaîne de caractère étaient aussi autorisés).
Valeurs de retour
Retourne un tableau de valeurs représentant une seule colonne depuis le tableau d'entrée.
Historique
| Version | Description |
|---|---|
| 8.0.0 |
Les objets dans les colonnes indiqué par le paramètre index_key
ne seront plus convertie en chaîne de caractères et lanceront désormais
une TypeError à la place.
|
Exemples
Exemple #1 Récupère la colonne des prénoms
<?php
// Tableau représentant un jeu d'enregistrements issu d'une base de données
$records = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
),
array(
'id' => 5342,
'first_name' => 'Jane',
'last_name' => 'Jones',
),
array(
'id' => 5623,
'first_name' => 'Peter',
'last_name' => 'Doe',
)
);
$first_names = array_column($records, 'first_name');
print_r($first_names);
?>L'exemple ci-dessus va afficher :
Array
(
[0] => John
[1] => Sally
[2] => Jane
[3] => Peter
)
Exemple #2 Récupère la colonne des noms, indexé par la colonne "id"
<?php
// En utilisant le tableau de l'exemple #1
$last_names = array_column($records, 'last_name', 'id');
print_r($last_names);
?>L'exemple ci-dessus va afficher :
Array
(
[2135] => Doe
[3245] => Smith
[5342] => Jones
[5623] => Doe
)
Exemple #3 Récupère la colonne des username depuis la propriété publique "username" d'un objet
<?php
class User
{
public $username;
public function __construct(string $username)
{
$this->username = $username;
}
}
$users = [
new User('user 1'),
new User('user 2'),
new User('user 3'),
];
print_r(array_column($users, 'username'));
?>L'exemple ci-dessus va afficher :
Array
(
[0] => user 1
[1] => user 2
[2] => user 3
)
Exemple #4 Récupère la colonne nom depuis la propriété privée "name" d'un objet en utilisant la méthode magique __get().
<?php
class Person
{
private $name;
public function __construct(string $name)
{
$this->name = $name;
}
public function __get($prop)
{
return $this->$prop;
}
public function __isset($prop) : bool
{
return isset($this->$prop);
}
}
$people = [
new Person('Fred'),
new Person('Jane'),
new Person('John'),
];
print_r(array_column($people, 'name'));
?>L'exemple ci-dessus va afficher :
Array
(
[0] => Fred
[1] => Jane
[2] => John
)
add a note
User Contributed Notes 31 notes
mohanrajnr at gmail dot com ¶
9 years ago
opencart dot ocfilter at gmail dot com ¶
1 year ago
Array multiple columns:
<?php
function array_columns() {
$args = func_get_args();
$array = array_shift($args);
if (!$args) {
return $array;
}
$keys = array_flip($args);
return array_map(function($element) use($keys) {
return array_intersect_key($element, $keys);
}, $array);
}
?>
EXAMPLE:
<?php
$products = [
[
'id' => 2,
'name' => 'Phone',
'price' => 210.3
],
[
'id' => 3,
'name' => 'Laptop',
'price' => 430.12
]
];
print_r(array_columns($products, 'name', 'price'));
?>
Output:
Array
(
[0] => Array
(
[name] => Phone
[price] => 210.3
)
[1] => Array
(
[name] => Laptop
[price] => 430.12
)
)
WARrior ¶
11 years ago
You can also use array_map fucntion if you haven't array_column().
example:
$a = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
)
);
array_column($a, 'last_name');
becomes
array_map(function($element){return $element['last_name'];}, $a);
balbuf ¶
6 years ago
This function does not preserve the original keys of the array (when not providing an index_key).
You can work around that like so:
<?php
// instead of
array_column($array, 'column');
// to preserve keys
array_combine(array_keys($array), array_column($array, 'column'));
?>
yangmeishu at live dot com ¶
4 years ago
Please note that if you use array_column to reset the index, when the index value is null, there will be different results in different PHP versions, examples
<?php
$array = [
[
'name' =>'Bob',
'house' =>'big',
],
[
'name' =>'Alice',
'house' =>'small',
],
[
'name' =>'Jack',
'house' => null,
],
];
var_dump(array_column($array,null,'house'));
On 5.6.30, 7.0.0, 7.2.0 (not limited to) get the following results
array(3) {
["big"]=>
array(2) {
["name"]=>
string(3) "Bob"
["house"]=>
string(3) "big"
}
["small"]=>
array(2) {
["name"]=>
string(5) "Alice"
["house"]=>
string(5) "small"
}
[0]=>
array(2) {
["name"]=>
string(4) "Jack"
["house"]=>
NULL
}
}
The new index, null will be converted to int, and can be incremented according to the previous index, that is, if Alice "house" is also null, then Alice's new index is "0", Jack's new index is "1"
On 7.1.21, 7.2.18, 7.4.8 (not limited to) will get the following results
array(3) {
["Big"]=>
array(2) {
["name"]=>
string(3) "Bob"
["house"]=>
string(3) "Big"
}
["small"]=>
array(2) {
["name"]=>
string(5) "Alice"
["house"]=>
string(5) "small"
}
[""]=>
array(2) {
["name"]=>
string(4) "Jack"
["house"]=>
NULL
}
}
The new index null will be converted to an empty string
till at etill dot net ¶
9 years ago
Some remarks not included in the official documentation.
1) array_column does not support 1D arrays, in which case an empty array is returned.
2) The $column_key is zero-based.
3) If $column_key extends the valid index range an empty array is returned.
nino at recgr dot com ¶
8 years ago
array_column implementation that works on multidimensional arrays (not just 2-dimensional):
<?php
function array_column_recursive(array $haystack, $needle) {
$found = [];
array_walk_recursive($haystack, function($value, $key) use (&$found, $needle) {
if ($key == $needle)
$found[] = $value;
});
return $found;
}
Taken from https://github.com/NinoSkopac/array_column_recursive
ff2 AT hotmail DOT co DOT uk ¶
6 years ago
Because the function was not available in my version of PHP, I wrote my own version and extended it a little based on my needs.
When you give an $indexkey value of -1 it preserves the associated array key values.
EXAMPLE:
$sample = array(
'test1' => array(
'val1' = 10,
'val2' = 100
),
'test2' => array(
'val1' = 20,
'val2' = 200
),
'test3' => array(
'val1' = 30,
'val2' = 300
)
);
print_r(array_column_ext($sample,'val1'));
OUTPUT:
Array
(
[0] => 10
[1] => 20
[2] => 30
)
print_r(array_column_ext($sample,'val1',-1));
OUTPUT:
Array
(
['test1'] => 10
['test2'] => 20
['test3'] => 30
)
print_r(array_column_ext($sample,'val1','val2'));
OUTPUT:
Array
(
[100] => 10
[200] => 20
[300] => 30
)
<?php
function array_column_ext($array, $columnkey, $indexkey = null) {
$result = array();
foreach ($array as $subarray => $value) {
if (array_key_exists($columnkey,$value)) { $val = $array[$subarray][$columnkey]; }
else if ($columnkey === null) { $val = $value; }
else { continue; }
if ($indexkey === null) { $result[] = $val; }
elseif ($indexkey == -1 || array_key_exists($indexkey,$value)) {
$result[($indexkey == -1)?$subarray:$array[$subarray][$indexkey]] = $val;
}
}
return $result;
}
?>
miguelfzarth at gmail dot com ¶
8 years ago
<?php
# for PHP < 5.5
# AND it works with arrayObject AND array of objects
if (!function_exists('array_column')) {
function array_column($array, $columnKey, $indexKey = null)
{
$result = array();
foreach ($array as $subArray) {
if (is_null($indexKey) && array_key_exists($columnKey, $subArray)) {
$result[] = is_object($subArray)?$subArray->$columnKey: $subArray[$columnKey];
} elseif (array_key_exists($indexKey, $subArray)) {
if (is_null($columnKey)) {
$index = is_object($subArray)?$subArray->$indexKey: $subArray[$indexKey];
$result[$index] = $subArray;
} elseif (array_key_exists($columnKey, $subArray)) {
$index = is_object($subArray)?$subArray->$indexKey: $subArray[$indexKey];
$result[$index] = is_object($subArray)?$subArray->$columnKey: $subArray[$columnKey];
}
}
}
return $result;
}
}
?>
Hiranmoy Chatterjee ¶
2 years ago
The following function may be useful to create columns from all values of indexed arrays:
<?php
function array_column_all(array $arrays): array
{
$output = [];
$columnCount = count($arrays[0]);
for ($i = 0; $i < $columnCount; $i++)
{
$output [] = array_column($arrays, $i);
}
return $output;
}
?>
Use:
-----
<?php
array_column_all(
[
['A1', 'A2', 'A3'],
['B1', 'B2', 'B3'],
['C1', 'C2', 'C3'],
]
);
?>
This will output:
-------------------
Array
(
[0] => Array
(
[0] => A1
[1] => B1
[2] => C1
)
[1] => Array
(
[0] => A2
[1] => B2
[2] => C2
)
[2] => Array
(
[0] => A3
[1] => B3
[2] => C3
)
)
Carlos Granados ¶
8 years ago
Here's a neat little snippet for filtering a set of records based on a the value of a column:
<?php
function dictionaryFilterList(array $source, array $data, string $column) : array
{
$new = array_column($data, $column);
$keep = array_diff($new, $source);
return array_intersect_key($data, $keep);
}
// Usage:
$users = [
['first_name' => 'Jed', 'last_name' => 'Lopez'],
['first_name' => 'Carlos', 'last_name' => 'Granados'],
['first_name' => 'Dirty', 'last_name' => 'Diana'],
['first_name' => 'John', 'last_name' => 'Williams'],
['first_name' => 'Betty', 'last_name' => 'Boop'],
['first_name' => 'Dan', 'last_name' => 'Daniels'],
['first_name' => 'Britt', 'last_name' => 'Anderson'],
['first_name' => 'Will', 'last_name' => 'Smith'],
['first_name' => 'Magic', 'last_name' => 'Johnson'],
];
var_dump(dictionaryFilterList(['Dirty', 'Dan'], $users, 'first_name'));
// Outputs:
[
['first_name' => 'Jed', 'last_name' => 'Lopez'],
['first_name' => 'Carlos', 'last_name' => 'Granados'],
['first_name' => 'John', 'last_name' => 'Williams'],
['first_name' => 'Betty', 'last_name' => 'Boop'],
['first_name' => 'Britt', 'last_name' => 'Anderson'],
['first_name' => 'Will', 'last_name' => 'Smith'],
['first_name' => 'Magic', 'last_name' => 'Johnson']
]
?>
Anonymous ¶
8 years ago
I added a little more functionality to the more popular answers here to support the $index_key parameter for PHP < 5.5
<?php
// for php < 5.5
if (!function_exists('array_column')) {
function array_column($input, $column_key, $index_key = null) {
$arr = array_map(function($d) use ($column_key, $index_key) {
if (!isset($d[$column_key])) {
return null;
}
if ($index_key !== null) {
return array($d[$index_key] => $d[$column_key]);
}
return $d[$column_key];
}, $input);
if ($index_key !== null) {
$tmp = array();
foreach ($arr as $ar) {
$tmp[key($ar)] = current($ar);
}
$arr = $tmp;
}
return $arr;
}
}
?>
antonfedonjuk at gmail dot com ¶
9 years ago
My version is closer to the original than http://github.com/ramsey/array_column
<?php
/**
* Provides functionality for array_column() to projects using PHP earlier than
* version 5.5.
* @copyright (c) 2015 WinterSilence (http://github.com/WinterSilence)
* @license MIT
*/
if (!function_exists('array_column')) {
/**
* Returns an array of values representing a single column from the input
* array.
* @param array $array A multi-dimensional array from which to pull a
* column of values.
* @param mixed $columnKey The column of values to return. This value may
* be the integer key of the column you wish to retrieve, or it may be
* the string key name for an associative array. It may also be NULL to
* return complete arrays (useful together with index_key to reindex
* the array).
* @param mixed $indexKey The column to use as the index/keys for the
* returned array. This value may be the integer key of the column, or
* it may be the string key name.
* @return array
*/
function array_column(array $array, $columnKey, $indexKey = null)
{
$result = array();
foreach ($array as $subArray) {
if (!is_array($subArray)) {
continue;
} elseif (is_null($indexKey) && array_key_exists($columnKey, $subArray)) {
$result[] = $subArray[$columnKey];
} elseif (array_key_exists($indexKey, $subArray)) {
if (is_null($columnKey)) {
$result[$subArray[$indexKey]] = $subArray;
} elseif (array_key_exists($columnKey, $subArray)) {
$result[$subArray[$indexKey]] = $subArray[$columnKey];
}
}
}
return $result;
}
}
?>
benjam ¶
8 years ago
Note that this function will return the last entry when possible keys are duplicated.
<?php
$array = array(
array(
'1-1',
'one',
'one',
),
array(
'1-2',
'two',
'one',
),
);
var_dump(array_column($array, $value = 0, $index = 1));
var_dump(array_column($array, $value = 0, $index = 2));
// returns:
/*
array (size=2)
'one' => string '1-1' (length=3)
'two' => string '1-2' (length=3)
array (size=1)
'one' => string '1-2' (length=3)
*/
?>
1184427175 at qq dot com ¶
7 years ago
//php < 5.5
if(function_exists('array_column'))
{
function array_column($arr_data, $col)
{
$result = array_map(function($arr){return $arr[$col]}, $arr_data);
return $result;
}
}
Rumour ¶
1 year ago
If you want to preserve the array keys AND you want it to work on both object properties and array elements AND you want it to work if some of the arrays/objects in the array do not have the given key/property defined, basically the most ROBUST version you can get, yet quick enough:
<?php
function array_column_keys(array|ArrayAccess $arr, string $col) {
// like array_columns but keeps the keys
//to make it work for objects and arrays
return array_map(fn($e) => (is_countable($e) ? ($e[$col]??null) : null) ?: (is_object($e) ? $e->$col : null), $arr);
}
?>
If a key/property is undefined, the value in the result array will be NULL. You can use array_filter() to filter those out if needed.
<?php
class a {
public string $a = 'property a';
public string $b = 'property b';
}
$a1 = new a;
$a2 = new a;
$a2->a = 'plop';
$b = ['one'=> ['a'=>'plop'],
3 => $a1,
4 => $a2,
5 =>[],
'kud'=>new a];
return array_column_keys($b, 'a');
?>
Returns:
Array
(
[one] => plop
[3] => property a
[4] => something else
[5] =>
[kud] => property a
)
oleg dot bolden at gmail dot com ¶
2 years ago
Index_key is safely applicable only in cases when corresponding values of this index are unique through over the array. Otherwise only the latest element of the array with the same index_key value will be picked up.
<?php
$records = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => 'Doe',
'company_id' => 1,
),
array(
'id' => 3245,
'first_name' => 'Sally',
'last_name' => 'Smith',
'company_id' => 1,
),
array(
'id' => 5342,
'first_name' => 'Jane',
'last_name' => 'Jones',
'company_id' => 1,
),
array(
'id' => 5623,
'first_name' => 'Peter',
'last_name' => 'Doe',
'company_id' => 2,
)
);
$first_names = array_column($records, 'first_name', 'company_id');
print_r($first_names);
?>
The above example will output:
<?php
Array
(
[1] => Jane
[2] => Peter
)
?>
To group values by the same `index_key` in arrays one can use simple replacement for the `array_column` like below example function:
<?php
function arrayed_column(array $array, int|string $column_key, int|string $index_key) {
$output = [];
foreach ($array as $item) {
$output[$item['index_key']][] = $item['column_key'];
}
return $output;
}
$first_names = arrayed_column($records, 'first_name', 'company_id');
print_r($first_names);
?>
The output:
<?php
Array
(
[1] => Array
(
[0] => John
[1] => Sally
[2] => Jane
)
[2] => Array
(
[0] =>Peter
)
)
?>
Sbastien ¶
2 years ago
The counterpart of array_column(), namely create an array from columns, can be done with array_map() :
<?php
// Columns
$lastnames = ['Skywalker', 'Organa', 'Kenobi'];
$firstnames = ['Luke', 'Leia', 'Obiwan'];
// Columns to array
$characters = array_map(
fn ($l, $f) => ['lastname' => $l, 'firstname' => $f],
$lastnames, $firstnames
);
print_r($characters);
/*
[
0 => ['lastname' => 'Skywalker', 'firstname' => 'Luke']
1 => ['lastname' => 'Organa', 'firstname' => 'Leia']
2 => ['lastname' => 'Kenobi', 'firstname' => 'Obiwan']
]
*/
info at mobger dot de ¶
1 year ago
If you want to rearrage an array with two layers (perhaps from database-requests), then use 'array_walk' instead:
<?php
$yamlList = [
['title' => 'hallo ich', 'identifier' => 'ich', 'Klaus'=> 'doof',],
['title' => 'hallo du', 'identifier' => 'du', 'Klaus'=> 'doof',],
['title' => 'hallo er', 'identifier' => 'er', 'Klaus'=> 'doof',],
];
echo ('Input'."\n".print_r($yamlList,true)."\n");
array_walk($yamlList, function (&$value, $key) {
$value = [
$value['title'],
$value['identifier'],
];
});
echo ("\n".'Output'."\n".print_r($yamlList,true)."\n");
?>
The Result
===========
...
Output
Array
(
[0] => Array
(
[0] => hallo ich
[1] => ich
)
[1] => Array
(
[0] => hallo du
[1] => du
)
[2] => Array
(
[0] => hallo er
[1] => er
)
)
Nolan chou ¶
8 years ago
if (!function_exists('array_column'))
{
function array_column($input, $column_key=null, $index_key=null)
{
$result = array();
$i = 0;
foreach ($input as $v)
{
$k = $index_key === null || !isset($v[$index_key]) ? $i++ : $v[$index_key];
$result[$k] = $column_key === null ? $v : (isset($v[$column_key]) ? $v[$column_key] : null);
}
return $result;
}
}
katrinaelaine6 at gmail dot com ¶
7 years ago
array_column() will return duplicate values.
Instead of having to use array_unique(), use the $index_key as a hack.
**Caution: This may get messy when setting the $column_key and/or $index_key as integers.**
<?php
$records = [
[ 'id' => 2135, 'first_name' => 'John' ],
[ 'id' => 3245, 'first_name' => 'Sally' ],
[ 'id' => 5342, 'first_name' => 'Jane' ],
[ 'id' => 5623, 'first_name' => 'Peter' ],
[ 'id' => 6982, 'first_name' => 'Sally' ]
];
print_r(array_unique(array_column($records, 'first_name')));
// Force uniqueness by making the key the value.
print_r(array_column($records, 'first_name', 'first_name'));
print_r(array_column($records, 'id', 'first_name'));
// Returns
/*
Array
(
[0] => John
[1] => Sally
[2] => Jane
[3] => Peter
)
Array
(
[John] => John
[Sally] => Sally
[Jane] => Jane
[Peter] => Peter
)
Array
(
[John] => 2135
[Sally] => 6982
[Jane] => 5342
[Peter] => 5623
)
*/
?>
hypxm at qq dot com ¶
10 years ago
a simple solution:
function arrayColumn(array $array, $column_key, $index_key=null){
if(function_exists('array_column ')){
return array_column($array, $column_key, $index_key);
}
$result = [];
foreach($array as $arr){
if(!is_array($arr)) continue;
if(is_null($column_key)){
$value = $arr;
}else{
$value = $arr[$column_key];
}
if(!is_null($index_key)){
$key = $arr[$index_key];
$result[$key] = $value;
}else{
$result[] = $value;
}
}
return $result;
}
kaspar dot wilbuer at web dot de ¶
8 years ago
If you need to extract more than one column from an array, you can use array_intersect_key on each element, like so:
function array_column_multi(array $input, array $column_keys) {
$result = array();
$column_keys = array_flip($column_keys);
foreach($input as $key => $el) {
$result[$key] = array_intersect_key($el, $column_keys);
}
return $result;
}
kiler129 @ nowhere ¶
9 years ago
Please note this function accepts 2D-arrays ONLY, and silently returns empty array when non-array argument is provided.
Code:
class testObject {
public $a = 123;
}
$testArray = [new testObject(), new testObject(), new testObject()];
$result = array_column($testArray, 'a')); //array(0) { }
marianbucur17 at yahoo dot com ¶
9 years ago
If array_column is not available you can use the following function, which also has the $index_key parameter:
if (!function_exists('array_column')) {
function array_column($array, $column_key, $index_key = null)
{
return array_reduce($array, function ($result, $item) use ($column_key, $index_key)
{
if (null === $index_key) {
$result[] = $item[$column_key];
} else {
$result[$item[$index_key]] = $item[$column_key];
}
return $result;
}, []);
}
}
myles at smyl dot es ¶
10 years ago
This didn't work for me recursively and needed to come up with a solution.
Here's my solution to the function:
if ( ! function_exists( 'array_column_recursive' ) ) {
/**
* Returns the values recursively from columns of the input array, identified by
* the $columnKey.
*
* Optionally, you may provide an $indexKey to index the values in the returned
* array by the values from the $indexKey column in the input array.
*
* @param array $input A multi-dimensional array (record set) from which to pull
* a column of values.
* @param mixed $columnKey The column of values to return. This value may be the
* integer key of the column you wish to retrieve, or it
* may be the string key name for an associative array.
* @param mixed $indexKey (Optional.) The column to use as the index/keys for
* the returned array. This value may be the integer key
* of the column, or it may be the string key name.
*
* @return array
*/
function array_column_recursive( $input = NULL, $columnKey = NULL, $indexKey = NULL ) {
// Using func_get_args() in order to check for proper number of
// parameters and trigger errors exactly as the built-in array_column()
// does in PHP 5.5.
$argc = func_num_args();
$params = func_get_args();
if ( $argc < 2 ) {
trigger_error( "array_column_recursive() expects at least 2 parameters, {$argc} given", E_USER_WARNING );
return NULL;
}
if ( ! is_array( $params[ 0 ] ) ) {
// Because we call back to this function, check if call was made by self to
// prevent debug/error output for recursiveness :)
$callers = debug_backtrace();
if ( $callers[ 1 ][ 'function' ] != 'array_column_recursive' ){
trigger_error( 'array_column_recursive() expects parameter 1 to be array, ' . gettype( $params[ 0 ] ) . ' given', E_USER_WARNING );
}
return NULL;
}
if ( ! is_int( $params[ 1 ] )
&& ! is_float( $params[ 1 ] )
&& ! is_string( $params[ 1 ] )
&& $params[ 1 ] !== NULL
&& ! ( is_object( $params[ 1 ] ) && method_exists( $params[ 1 ], '__toString' ) )
) {
trigger_error( 'array_column_recursive(): The column key should be either a string or an integer', E_USER_WARNING );
return FALSE;
}
if ( isset( $params[ 2 ] )
&& ! is_int( $params[ 2 ] )
&& ! is_float( $params[ 2 ] )
&& ! is_string( $params[ 2 ] )
&& ! ( is_object( $params[ 2 ] ) && method_exists( $params[ 2 ], '__toString' ) )
) {
trigger_error( 'array_column_recursive(): The index key should be either a string or an integer', E_USER_WARNING );
return FALSE;
}
$paramsInput = $params[ 0 ];
$paramsColumnKey = ( $params[ 1 ] !== NULL ) ? (string) $params[ 1 ] : NULL;
$paramsIndexKey = NULL;
if ( isset( $params[ 2 ] ) ) {
if ( is_float( $params[ 2 ] ) || is_int( $params[ 2 ] ) ) {
$paramsIndexKey = (int) $params[ 2 ];
} else {
$paramsIndexKey = (string) $params[ 2 ];
}
}
$resultArray = array();
foreach ( $paramsInput as $row ) {
$key = $value = NULL;
$keySet = $valueSet = FALSE;
if ( $paramsIndexKey !== NULL && array_key_exists( $paramsIndexKey, $row ) ) {
$keySet = TRUE;
$key = (string) $row[ $paramsIndexKey ];
}
if ( $paramsColumnKey === NULL ) {
$valueSet = TRUE;
$value = $row;
} elseif ( is_array( $row ) && array_key_exists( $paramsColumnKey, $row ) ) {
$valueSet = TRUE;
$value = $row[ $paramsColumnKey ];
}
$possibleValue = array_column_recursive( $row, $paramsColumnKey, $paramsIndexKey );
if ( $possibleValue ) {
$resultArray = array_merge( $possibleValue, $resultArray );
}
if ( $valueSet ) {
if ( $keySet ) {
$resultArray[ $key ] = $value;
} else {
$resultArray[ ] = $value;
}
}
}
return $resultArray;
}
}
greensea ¶
8 years ago
<?php
if (!function_exists('array_column')) {
function array_column($input, $column_key, $index_key = NULL) {
if (!is_array($input)) {
trigger_error(__FUNCTION__ . '() expects parameter 1 to be array, ' . gettype($input) . ' given', E_USER_WARNING);
return FALSE;
}
$ret = array();
foreach ($input as $k => $v) {
$value = NULL;
if ($column_key === NULL) {
$value = $v;
}
else {
$value = $v[$column_key];
}
if ($index_key === NULL || !isset($v[$index_key])) {
$ret[] = $value;
}
else {
$ret[$v[$index_key]] = $value;
}
}
return $ret;
}
}
?>
robbieaverill[at]gmail.com ¶
9 years ago
Another option for older PHP versions (pre 5.5.0) is to use array_walk():
<?php
$array = array(
array('some' => 'var', 'foo' => 'bar'),
array('some' => 'var', 'foo' => 'bar'),
array('some' => 'var', 'foo' => 'bar')
);
array_walk($array, function(&$value, $key, $return) {
$value = $value[$return];
}, 'foo');
print_r($array);
// Array
// (
// [0] => bar
// [1] => bar
// [2] => bar
// )
?>
coviex ¶
10 years ago
Value for existing key in the resulting array is rewritten with new value if it exists in another source sub-array.
robsonvnasc at gmail dot com ¶
7 years ago
Retrieve multiple columns from an array:
$columns_wanted = array('foo','bar');
$array = array('foo'=>1,'bar'=>2,'foobar'=>3);
$filtered_array = array_intersect_key(array_fill_keys($columns_wanted,''));
//filtered_array
// array('foo'=>1,'bar'=>2);
Dominik59 ¶
7 years ago
Presented function is good when You want to flatten nested array base on only one column, but if You want to flatten whole array You can use this method:
/**
* Method that transforms nested array into the flat one in below showed way:
* [
* [
* [0]=>'today',
* ],
* [
* [0]=>'is',
* [1]=>'very',
* [2]=> [
* [0]=>'warm'
* ],
* ],
* ]
*
* Into:
*
* ['today','is','very','warm']
*
* @param $input
* @return array
*/
private function transformNestedArrayToFlatArray($input)
{
$output_array = [];
if (is_array($input)) {
foreach ($input as $value) {
if (is_array($value)) {
$output_array = array_merge($output_array, $this->transformNestedArrayToFlatArray($value));
} else {
array_push($output_array, $value);
}
}
} else {
array_push($output_array, $input);
}
return $output_array;
}
