(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.
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
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
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:
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 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");.
//array_diff_uassoc for multidimenssional array
$color_1=array('a'=>'white','b'=>'red','c'=>array('a'=>'green','b'=>'blue','c'=>'yellow'));
$color_2=array('a'=>'white','b'=>'red','c'=>array('a'=>'white','b'=>'red','c'=>'yellow'));
function key_compare($a,$b){
if($a===$b) return 0;
return($a>$b)?1:-1;
}
print_r(array_diff_uassoc($color_1['c'], $color_2['c'],"key_compare"));
//Output
Array
(
[a] => green
[b] => blue
)