The SplDoublyLinkedList::offsetExists() function is an inbuilt function in PHP which is used to check whether the given index exists or not.
Syntax:
bool SplDoublyLinkedList::offsetExists( $index )
Parameters: This function accepts a single parameter $index which holds the index value to be checked.
Return Value: It returns True if given index exist otherwise return False.
Below programs illustrate the SplDoublyLinkedList::offsetExists() function in PHP:
Program 1:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList;
// Use SplDoublyLinkedList::add() function to // add elements to the SplDoublyLinkedList $list ->add(0, 30);
$list ->add(1, 20);
$list ->add(2, 30);
$list ->add(3, "Geeks" );
$list ->add(4, 'G' );
$list -> rewind ();
// Use SplDoublyLinkedList::offsetExists() function // to check index exist or not var_dump( $list ->offsetExists(2));
var_dump( $list ->offsetExists(10));
?> |
Output:
bool(true) bool(false)
Program 2:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList();
// Use SplDoublyLinkedList::push() function to // add elements to the SplDoublyLinkedList $list ->push(1);
$list ->push(2);
$list ->push(3);
$list ->push(8);
$list ->push(5);
// Use SplDoublyLinkedList::offsetExists() function // to check index exist or not var_dump( $list ->offsetExists(3));
var_dump( $list ->offsetExists(15));
?> |
Output:
bool(true) bool(false)
Reference: https://www.php.net/manual/en/spldoublylinkedlist.offsetexists.php