Опис

array_diff(array $array, array ...$arrays): array

Compares array against one or more other arrays and returns the values in array that are not present in any of the other arrays.

Параметри

array: The array to compare from
arrays: Arrays to compare against

Значення, що повертаються

Returns an array containing all the entries from array that are not present in any of the other arrays. Keys in the array array are preserved.

Журнал змін

Версія Опис

8.0.0 Тепер ця функція може викликатись лише з одним параметром. Раніше потрібні були щонайменше два.

Версія	Опис
8.0.0	Тепер ця функція може викликатись лише з одним параметром. Раніше потрібні були щонайменше два.

Приклади

Приклад #1 array_diff() example

<?php
$array1 = array("a" => "green", "red", "blue", "red");
$array2 = array("b" => "green", "yellow", "red");
$result = array_diff($array1, $array2);

print_r($result);
?>

Multiple occurrences in $array1 are all treated the same way. This will output :

Array
(
    [1] => blue
)

Two elements are considered equal if and only if (string) $elem1 === (string) $elem2. That is, when the string representation is the same.

Приклад #2 array_diff() example with non-matching types

<?php
// This will generate a Notice that an array cannot be cast to a string.
$source = [1, 2, 3, 4];
$filter = [3, 4, [5], 6];
$result = array_diff($source, $filter);

// Whereas this is fine, since the objects can cast to a string.
class S {
  private $v;

  public function __construct(string $v) {
    $this->v = $v;
  }

  public function __toString() {
    return $this->v;
  }
}

$source = [new S('a'), new S('b'), new S('c')];
$filter = [new S('b'), new S('c'), new S('d')];

$result = array_diff($source, $filter);

// $result now contains one instance of S('a');
var_dump($result);
?>

To use an alternate comparison function, see array_udiff().

Примітки

Зауваження:
This function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using array_diff($array1[0], $array2[0]);.

Прогляньте також

array_diff_assoc() - Computes the difference of arrays with additional index check
array_udiff() - Computes the difference of arrays by using a callback function for data comparison
array_intersect() - Computes the intersection of arrays
array_intersect_assoc() - Computes the intersection of arrays with additional index check