PHP SplDoublyLinkedList key () function

PHP

Syntax:
mixed SplDoublyLinkedList::key (void)
Parameters:this function takes no parameters.Return value:returns the index of the current node.The following programs illustrate the functionS plDoublyLinkedList::key()in PHP:Program 1:  
// Declare an empty SplDoublyLinkedList $list = new SplDoublyLinkedList;  
// Use the SplDoublyLinkedList::add() function for
// add elements to SplDoublyLinkedList $list -> add (0, 30); $list -> add (1, 20); $list -> add (2, 30); $list -> add (3, " Geeks " ); $list -> add (4, ` G` ); $list -> rewind ();  
// Use the SplDoublyLinkedList::key() function
// to get the key var_dump ( $list -> key());  
// Use the next() function to enlarge
// index value $list -> next();  
// Use the SplDoublyLinkedList::key() function
// to get the key var_dump ( $list -> key());  
?>
Exit:
int (0 ) int (1)
Program 2:  
// Declare an empty SplDoublyLinkedList $list = new SplDoublyLinkedList();  
// Use the SplDoublyLinkedList::push() function for
// add elements to SplDoublyLinkedList $list -> push (1); $list -> push (2); $list -> push (3); $list -> push (8); $list -> push (5); $list -> rewind ();  
// Use the SplDoublyLinkedList::key() function
// to get the key var_dump ( $list -> key());  
// Use the next() function to enlarge
// index value $list -> next(); $list -> next(); $list -> next();  
// Use the SplDoublyLinkedList::key() function
// to get the key var_dump ( $list -> key());  
?>
Exit:
int (0 ) int (3)
Link: https:// www .php.net / manual / en / spldoublylinkedlist.key.php



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