array_diff_ukey
Computes the difference of arrays using a callback function on the keys for comparison
Description
array array_diff_ukey(array $array, array ...$arrays, callable $key_compare_func)
Unlike array_diff_key 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
-
The 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.
int callback(mixed $a, mixed $b)
Caution
Returning non-integer values from the comparison
function, such as float, will result in an internal cast to
int of the callback's return value. So values such as
0.99 and 0.1 will both be cast to an
integer value of 0, which will compare such values as equal.
Return Values
Returns an array containing all the entries from
array that are not present in any of the other arrays.
Examples
Example #1 array_diff_ukey example
<?php
function key_compare_func($key1, $key2)
{
if ($key1 == $key2)
return 0;
else if ($key1 > $key2)
return 1;
else
return -1;
}
$array1 = array('blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8);
var_dump(array_diff_ukey($array1, $array2, 'key_compare_func'));
?>
The above example will output:
array(2) {
["red"]=>
int(2)
["purple"]=>
int(4)
}
Notes
Note:
This function only checks one dimension of a n-dimensional
array. Of course you can check deeper dimensions by using
array_diff_ukey($array1[0], $array2[0], 'callback_func');.
See Also
- array_diff
- array_udiff
- array_diff_assoc
- array_diff_uassoc
- array_udiff_assoc
- array_udiff_uassoc
- array_diff_key
- array_intersect
- array_intersect_assoc
- array_intersect_uassoc
- array_intersect_key
- array_intersect_ukey