(PHP 5 >= 5.1.0, PHP 7)
array_intersect_ukey — Computes the intersection of arrays using a callback function on the keys for comparison
$array1
, array $array2
[, array $...
], callable $key_compare_func
)
array_intersect_ukey() returns an array
containing all the values of array1
which have matching keys that are present in all the arguments.
array1
Initial array for comparison of the arrays.
array2
First array to compare keys against.
...
Variable list of array arguments to compare keys against.
key_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second. Note that before PHP 7.0.0 this integer had to be in the range from -2147483648 to 2147483647.
Returns the values of array1
whose keys exist
in all the arguments.
Example #1 array_intersect_ukey() example
<?php
function key_compare_func($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);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8);
var_dump(array_intersect_ukey($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
.