PHP key_exists() Function
PHP key_exists() Function
The key_exists() function in PHP checks if the specified key or index exists in the array or not.
Syntax
key_exists ( mixed $key , array $array )
Parameter
key(required)- This parameter represents the value to check.
array(required)- This parameter signifies an input array with keys to check.
Return
This function returns a Boolean value TRUE on success or FALSE on failure.
Example 1
'first', 2=>'second',3 => 'third',4=>'fourth',5=>'fifth'); // passing the key value $key= 3; // will check whether the key exists or not if (key_exists($key, $search_array)) { echo "The $key key element is present in the array"; } else { echo "The $key key element is not present in the array"; } ?>
Output
The 3 key element is present in the array
Example 2
'first', 2=>'second',3 => null, 4=>'fourth'); //printing the input array print_r($search_array); // passing the key value $key= 3; // will check whether the key exists or not if (key_exists($key, $search_array)) { echo "The $key key element is present in the array"; } else { echo "The $key key element is not present in the array"; } ?>
Output
The 3 key element is present in the array
Example 3
Output
The 3 key element is not present in the array