PHParray_intersect_key() Function
Example
Compare thekeys of two arrays, and return the matches:
<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","c"=>"blue","d"=>"pink");
$result=array_intersect_key($a1,$a2);
print_r($result);
?>
Try it Yourself »$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","c"=>"blue","d"=>"pink");
$result=array_intersect_key($a1,$a2);
print_r($result);
?>
Definition and Usage
The array_intersect_key() function comparesthe keys of two (or more) arrays, and returns the matches.
This function compares the keys of two or more arrays, and return an array that contains the entries fromarray1 that are present inarray2,array3, etc.
Syntax
array_intersect_key(array1, array2, array3, ...)
Parameter Values
| Parameter | Description |
|---|---|
| array1 | Required. The first array is the array that the others will be compared with |
| array2 | Required. An array to be compared with the first array |
| array3,... | Optional. An array to be compared with the first array |
Technical Details
| Return Value: | Returns an array containing the entries from array1 that are present in all of the other arrays |
|---|---|
| PHP Version: | 5.1.0+ |
More Examples
Example
Compare thekeys of two indexed arrays, and return the matches:
<?php
$a1=array("red","green","blue","yellow");
$a2=array("red","green","blue");
$result=array_intersect_key($a1,$a2);
print_r($result);
?>
Try it Yourself »$a1=array("red","green","blue","yellow");
$a2=array("red","green","blue");
$result=array_intersect_key($a1,$a2);
print_r($result);
?>
Example
Compare thekeys of three arrays, and return the matches:
<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("c"=>"yellow","d"=>"black","e"=>"brown");
$a3=array("f"=>"green","c"=>"purple","g"=>"red");
$result=array_intersect_key($a1,$a2,$a3);
print_r($result);
?>
Try it Yourself »$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("c"=>"yellow","d"=>"black","e"=>"brown");
$a3=array("f"=>"green","c"=>"purple","g"=>"red");
$result=array_intersect_key($a1,$a2,$a3);
print_r($result);
?>
❮ PHP Array Reference
