array_diff_ukey
(PHP 5 >= 5.1.0, PHP 7, PHP 8)
array_diff_ukey — Computes the difference of arrays using a callback function on the keys for comparison
Description
Compares the keys from array against the keys
from arrays and returns the difference.
This function is like array_diff() except the
comparison is done on the keys instead of the values.
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.
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() - Computes the difference of arrays
- array_udiff() - Computes the difference of arrays by using a callback function for data comparison
- array_diff_assoc() - Computes the difference of arrays with additional index check
- array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
- array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
- array_udiff_uassoc() - Computes the difference of arrays with additional index check, compares data and indexes by a callback function
- array_diff_key() - Computes the difference of arrays using keys for comparison
- array_intersect() - Computes the intersection of arrays
- array_intersect_assoc() - Computes the intersection of arrays with additional index check
- array_intersect_uassoc() - Computes the intersection of arrays with additional index check, compares indexes by a callback function
- array_intersect_key() - Computes the intersection of arrays using keys for comparison
- array_intersect_ukey() - Computes the intersection of arrays using a callback function on the keys for comparison
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