Home  >  Article  >  Backend Development  >  Definition and usage of PHP array_diff_key() function

Definition and usage of PHP array_diff_key() function

巴扎黑
巴扎黑Original
2017-05-24 14:25:461644browse

Definition and usage

array_diff_key() function is used to compare the key names of two (or more) arrays and return the difference.

This function compares the key names of two (or more) arrays and returns a difference array that includes everything in the compared array (array1) but not in any other parameter array (array2 or array3, etc.).

Syntax

array_diff_key(array1,array2,array3...);

Parameter description:

array1 Required. The first array to compare with other arrays. ​

array2 Required. The array to compare to the first array.

array3,... Optional. Additional array to compare with the first array.

Return value:

Returns a difference array that includes all elements in the compared array (array1) that are not in any other parameter array (array2) or array3, etc.).

Example display 1:

<!DOCTYPE html>
<html>
<body>

<?php
$a1=array("a"=>"red","b"=>"green","c"=>"blue");
$a2=array("a"=>"red","c"=>"blue","d"=>"pink");

$result=array_diff_key($a1,$a2);
print_r($result);
?>

</body>
</html>

Run result:

Array ( [b] => green )

Example display 2:

<!DOCTYPE html>
<html>
<body>
<?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");
$result=array_diff_key($a1,$a2,$a3);
print_r($result);
?>
</body>
</html>

Run result

Array ( [a] => red [b] => green )

The above is the detailed content of Definition and usage of PHP array_diff_key() function. For more information, please follow other related articles on the PHP Chinese website!

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn