Example
Compare the keys 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);
?>
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Definition and Usage
The array_intersect_key() function compares the 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 from array1 that are present in array2, array3, etc.
Syntax
array_intersect_key(array1,array2,array3...)
| 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 1
Compare the keys 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);
?>
Run example »
Example 2
Compare the keys 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);
?>
Run example »
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