array_uintersect(): intersection of arrays with Custom Comparison

array_uintersect(): custom value intersection

array_uintersect() finds common values using a user-supplied value comparison callback and preserves keys from the first array.

$first = [10, 20, 30];
$second = [10, 25, 30];
$result = array_uintersect($first, $second, fn($a, $b) => $a <=> $b);
print_r($result);

Return an integer comparison result from the callback rather than true or false.

The array_uintersect() function in PHP returns the intersection of arrays, using a custom callback function to compare values. It is useful when the comparison between array elements requires custom logic.

Syntax

array_uintersect(array $array1, array $array2, callable $callback): array

Example 1: Simple Intersection with Case-Insensitive Comparison

function caseInsensitiveCompare($a, $b) {
    return strcmp(strtolower($a), strtolower($b));
}

$array1 = ['APPLE', 'BANANA', 'CHERRY'];
$array2 = ['apple', 'ORANGE', 'cherry'];

$result = array_uintersect($array1, $array2, 'caseInsensitiveCompare');
print_r($result);

Output

Array
(
    [0] => APPLE
    [2] => CHERRY
)

Example 2: Intersection of Numeric Arrays with Custom Comparison

function numCompare($a, $b) {
    return $a - $b;
}

$array1 = [1, 2, 3, 4];
$array2 = [3, 4, 5, 6];

$result = array_uintersect($array1, $array2, 'numCompare');
print_r($result);

Output

Array
(
    [2] => 3
    [3] => 4
)

Conclusion

The array_uintersect() function provides flexibility in finding intersections between arrays by allowing custom comparison logic, making it highly versatile for different use cases.
array_intersect(): Intersection of two or more arrays Difference between arrays considering values
Array REFERENCE

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

About the author Watch on YouTube

Connect:

Subscribe to our YouTube Channel here

This article is written by plus2net.com team. https://www.plus2net.com

plus2net.com