In PHP7+ to find if a value is set in a multidimensional array with a fixed number of dimensions, simply use the Null Coalescing Operator: ??
So for a three dimensional array where you are not sure about any of the keys actually existing
<?php
// instead of:
$exists = array_key_exists($key1, $arr) && array_key_exists($key2, $arr[$key1]) && array_key_exists($key3, $arr[$key1][$key2]) ;
// use:
$exists = array_key_exists($key3, $arr[$key1][$key2]??[]) ;
?>| CARVIEW |
Select Language
HTTP/2 200
server: myracloud
date: Tue, 14 Oct 2025 07:01:32 GMT
content-type: text/html; charset=utf-8
content-language: en
permissions-policy: interest-cohort=()
x-frame-options: SAMEORIGIN
link: ; rel=shorturl
last-modified: Tue, 14 Oct 2025 06:08:42 GMT
content-encoding: gzip
vary: accept-encoding
expires: Tue, 14 Oct 2025 07:01:32 GMT
cache-control: max-age=0
PHP: array_key_exists - Manual
array_key_exists
(PHP 4 >= 4.0.7, PHP 5, PHP 7, PHP 8)
array_key_exists — Checks if the given key or index exists in the array
Description
array_key_exists() returns true if the
given key is set in the array.
key can be any value possible
for an array index.
Parameters
key-
Value to check.
array-
An array with keys to check.
Return Values
Returns true on success or false on failure.
Note:
array_key_exists() will search for the keys in the first dimension only. Nested keys in multidimensional arrays will not be found.
Changelog
| Version | Description |
|---|---|
| 8.0.0 |
The key parameter now accepts
bool, float, int,
null, resource, and
string as arguments.
|
| 8.0.0 |
Passing an object to the array parameter is no longer supported.
|
| 7.4.0 |
Passing an object to the array parameter has been deprecated. Use property_exists() instead.
|
Examples
Example #1 array_key_exists() example
<?php
$searchArray = ['first' => 1, 'second' => 4];
var_dump(array_key_exists('first', $searchArray));
?>The above example will output:
bool(true)
Example #2 array_key_exists() vs isset()
isset() does not return true for array keys
that correspond to a null value, while
array_key_exists() does.
<?php
$searchArray = ['first' => null, 'second' => 4];
var_dump(isset($searchArray['first']));
var_dump(array_key_exists('first', $searchArray));
?>The above example will output:
bool(false) bool(true)
See Also
- isset() - Determine if a variable is declared and is different than null
- array_keys() - Return all the keys or a subset of the keys of an array
- in_array() - Checks if a value exists in an array
- property_exists() - Checks if the object or class has a property
＋add a note
User Contributed Notes 3 notes
Rumour ¶
2 years ago
Julian ¶
2 years ago
When you want to check multiple array keys:
<?php
$array = [];
$array['a'] = '';
$array['b'] = '';
$array['c'] = '';
$array['d'] = '';
$array['e'] = '';
// all given keys a,b,c exists in the supplied array
var_dump(array_keys_exists(['a','b','c'], $array)); // bool(true)
function array_keys_exists(array $keys, array $array): bool
{
$diff = array_diff_key(array_flip($keys), $array);
return count($diff) === 0;
}
developerxyz852 at gmail dot com ¶
6 months ago
<?php
// Define an associative array
$userProfile = [
'name' => 'John Doe',
'email' => 'john.doe@example.com',
'age' => 30,
'country' => 'USA'
];
// Key to check
$keyToCheck = 'email';
// Use array_key_exists to check if the key exists in the array
if (array_key_exists($keyToCheck, $userProfile)) {
echo "The key '$keyToCheck' exists in the array with value: " . $userProfile[$keyToCheck];
} else {
echo "The key '$keyToCheck' does not exist in the array.";
}
?>
↑ and ↓ to navigate •
Enter to select •
Esc to close
Press Enter without
selection to search using Google