The array_intersect_ukey Function

The array_intersect_ukey function takes several arrays and a callback function to compare their keys. The first parameter is the main array, followed by the arrays for comparison. The last parameter is the callback function, which should compare keys and return an integer (less than, equal to, or greater than zero).

Syntax

array_intersect_ukey(array $array1, array $array2, ..., callable $key_compare_func): array

Example

Compare the keys of two arrays using a custom function:

<?php
	$array1 = ['a' => 1, 'b' => 2, 'c' => 3];
	$array2 = ['a' => 4, 'c' => 5, 'd' => 6];
	
	$res = array_intersect_ukey($array1, $array2, function($key1, $key2) {
		return strcmp($key1, $key2);
	});
	
	print_r($res);
?>

Code execution result:

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

Example

Comparing keys of three arrays with case sensitivity:

<?php
	$array1 = ['A' => 1, 'B' => 2, 'C' => 3];
	$array2 = ['a' => 4, 'B' => 5, 'C' => 6];
	$array3 = ['A' => 7, 'B' => 8, 'c' => 9];
	
	$res = array_intersect_ukey($array1, $array2, $array3, function($key1, $key2) {
		return strcmp($key1, $key2);
	});
	
	print_r($res);
?>

Code execution result:

['B' => 2]

The array_intersect_ukey Function

Syntax

Example

Example

See Also