Home/ Manual/ array / functions/ array_diff_uassoc

array_diff_uassoc

PHP function Edit on GitHub ✎

(PHP 5, PHP 7, PHP 8)

Computes the difference of arrays with additional index check which is performed by a user supplied callback function

Description

array_diff_uassoc(array $array, array ...$arrays, callable $key_compare_func): array

Compares array against arrays and returns the difference. Unlike array_diff() the array keys are used in the comparison.

Unlike array_diff_assoc() a user supplied callback function is used for the indices comparison, not internal function.

Parameters

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

Return Values

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

Examples

array_diff_uassoc() example

In this example the "a" => "green" pair is present in both arrays and thus it is not in the output from the function. Unlike this, the pair 0 => "red" is in the output because the key of "red" is automatically assigned to 0 in the first array, whereas it is assigned to 1 in the second array as the key 0 is already taken by yellow.

php

<?php
function key_compare_func($a, $b)
{
    return $a <=> $b;
}

$array1 = array("a" => "green", "b" => "brown", "c" => "blue", "red");
$array2 = array("a" => "green", "yellow", "red");
$result = array_diff_uassoc($array1, $array2, "key_compare_func");
print_r($result);
?>

The above example will output:

output

Array
(
    [b] => brown
    [c] => blue
    [0] => red
)

The equality of 2 indices is checked by the user supplied callback function.

Notes

Note

This function only checks one dimension of an n-dimensional array. It is possible to check deeper dimensions by using, for example, array_diff_uassoc($array1[0], $array2[0], "key_compare_func");.