(PHP 5, PHP 7, PHP 8)
array_diff_uassoc — Computes the difference of arrays with additional index check which is performed by a user supplied callback function
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.
arrayThe array to compare from
arraysArrays to compare against
key_compare_funcThe 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.
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.
Returns an array containing all the entries from
array that are not present in any of the other arrays.
Example #1 array_diff_uassoc() 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 in the second argument "red"
has key which is 1.
<?php
function key_compare_func($a, $b)
{
if ($a === $b) {
return 0;
}
return ($a > $b)? 1:-1;
}
$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:
Array
(
[b] => brown
[c] => blue
[0] => red
)
The equality of 2 indices is checked by the user supplied callback function.
Note:
This function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example,
array_diff_uassoc($array1[0], $array2[0], "key_compare_func");.