PHP Tutorial - PHP array_intersect_key() function compares the keys of two arrays, and return the matches
Definition
The array_intersect_key() function compares the keys of two or more arrays, and returns an array that contains the entries from array1 that are present in array2, array3, etc.
Syntax
PHP array_intersect_key() function has the following syntax.
array_intersect_key(array1,array2,array3...)Parameter
| Parameter | Is Required | Description |
|---|---|---|
| array1 | Required. | Array to be compared with |
| array2 | Required. | Array to be compared with array1 |
| array3,... | Optional. | Array to be compared with array1 |
Return
PHP array_intersect_key() function returns an array that contains the entries from array1 that are present in array2, array3, etc.
Example 1
Compare the keys of two indexed arrays, and return the matches:
<?php
$a1=array("a"=>"A","b"=>"B","c"=>"C","d"=>"Dog");
$a2=array("a"=>"B","b"=>"New B","c"=>"java2s.com");
$result=array_intersect_key($a1,$a2);
print_r($result);
?>
The code above generates the following result.
Example 2
Compare the keys of three arrays, and return the matches:
<?php
$a1=array("a"=>"A","b"=>"B","c"=>"C","d"=>"Dog");
$a2=array("a"=>"B","b"=>"New B","c"=>"java2s.com");
$a3=array("J"=>"java2s.com");
$result=array_intersect_key($a1,$a2,$a3);
print_r($result);
?>
The code above generates the following result.
