PHP array_intersect_ukey function

array_intersect_ukey

(PHP 5 >= 5.1.0RC1)

array_intersect_ukey -- Computes the intersection of arrays using a callback function on the keys for comparisonDescriptionarray array_intersect_ukey ( array array1, array array2 [, array ..., callback key_compare_func] )

array_intersect_ukey() returns an array
containing all the values of array1
which have matching keys that are present in all the arguments.

This comparison is done by a user supplied callback function.
It must return an integer less than, equal to, or greater than zero if the
first key is considered to be respectively less than, equal to, or
greater than the second.

Example 1. array_intersect_ukey() example

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_intersect_ukey($array1, $array2, 'key_compare_func'));

The above example will output:

array(2) {
["blue"]=>
int(1)
["green"]=>
int(3)
}

In our example you see that only the keys 'blue'
and 'green' are present in both arrays and thus
returned. Also notice that the values for the keys
'blue' and 'green' differ between
the two arrays. A match still occurs because only the keys are checked.
The values returned are those of array1.

See also array_diff(),
array_udiff()
array_diff_assoc(),
array_diff_uassoc(),
array_udiff_assoc(),
array_udiff_uassoc(),
array_diff_key(),
array_diff_ukey(),
array_intersect(),
array_intersect_assoc(),
array_intersect_uassoc() and
array_intersect_key().