array_intersect_key
Computes the intersection of arrays using keys for comparison
Description
array array_intersect_key(array $array, array ...$arrays)
Parameters
-
array
-
The array with master keys to check.
-
arrays
-
Arrays to compare keys against.
Return Values
Returns an associative array containing all the entries of
array which have keys that are present in all
arguments.
Examples
Example #1 array_intersect_key example
<?php
$array1 = array('blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4);
$array2 = array('green' => 5, 'blue' => 6, 'yellow' => 7, 'cyan' => 8);
var_dump(array_intersect_key($array1, $array2));
?>
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 array.
The two keys from the key => value pairs are
considered equal only if
(string) $key1 === (string) $key2 . In other words
a strict type check is executed so the string representation must be
the same.
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
- array_intersect_ukey