Syntax:bool array_key_exists ( mixed $key , array $search )
Description:Checks if the given key or index exists in the array
<?php $search_array = array('first' => 1, 'second' => 4); if (array_key_exists('first', $search_array)) { echo "The 'first' element is in the array"; } ?>OUTPUT
The 'first' element is in the array