PHP Manual: Computes the intersection of arrays, compares data by a callback function

Description

array array_uintersect(array $array, array ...$arrays, callable $value_compare_func)

Computes the intersection of arrays, compares data by a callback function.

Parameters

array

The first array.

arrays

Arrays to compare against.

value_compare_func

The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.

int callback(mixed $a, mixed $b)

Caution

Returning non-integer values from the comparison function, such as float, will result in an internal cast to int of the callback's return value. So values such as 0.99 and 0.1 will both be cast to an integer value of 0, which will compare such values as equal.

Caution

The sorting callback must handle any value from any array in any order, regardless of the order they were originally provided. This is because each individual array is first sorted before being compared against other arrays. For example:

<?php
$arrayA = ["string", 1];
$arrayB = [["value" => 1]];
// $item1 and $item2 can be any of "string", 1 or ["value" => 1]
$compareFunc = static function ($item1, $item2) {
    $value1 = is_string($item1) ? strlen($item1) : (is_array($item1) ? $item1["value"] : $item1);
    $value2 = is_string($item2) ? strlen($item2) : (is_array($item2) ? $item2["value"] : $item2);
    return $value1 <=> $value2;
};
?>

Return Values

Returns an array containing all the values of array that are present in all the arguments.

Examples

Example #1 array_uintersect example

<?php
$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "GREEN", "B" => "brown", "yellow", "red");

print_r(array_uintersect($array1, $array2, "strcasecmp"));
?>

The above example will output:

Array
(
    [a] => green
    [b] => brown
    [0] => red
)

array_uintersect

Description

Parameters

Return Values

Examples

See Also