The array_intersect_uassoc Function

The array_intersect_uassoc function compares arrays and returns elements that are present in all arrays, using a callback function for key comparison. The first parameter is the main array, the subsequent ones are arrays for comparison, and the last parameter is the callback function for key comparison.

Syntax

array_intersect_uassoc(array $array1, array $array2, ..., callable $key_compare_func): array;

Example

Let's compare two arrays with key check via a user-defined function:

<?php
	$array1 = ['a' => 1, 'b' => 2, 'c' => 3];
	$array2 = ['a' => 1, 'b' => 5, 'c' => 3];
	
	function compareKeys($a, $b) {
		return $a <=> $b;
	}
	
	$res = array_intersect_uassoc($array1, $array2, 'compareKeys');
	print_r($res);
?>

Code execution result:

['a' => 1, 'c' => 3]

Example

Let's compare three arrays with a user-defined key comparison function:

<?php
	$array1 = [1 => 'a', 2 => 'b', 3 => 'c'];
	$array2 = [1 => 'a', 4 => 'b', 3 => 'd'];
	$array3 = [1 => 'a', 3 => 'e'];
	
	function keyCompare($key1, $key2) {
		if ($key1 == $key2) {
			return 0;
		}
		return ($key1 < $key2) ? -1 : 1;
	}
	
	$res = array_intersect_uassoc($array1, $array2, $array3, 'keyCompare');
	print_r($res);
?>

Code execution result:

[1 => 'a']

The array_intersect_uassoc Function

Syntax

Example

Example

See Also