SplDoublyLinkedList::isEmpty

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

SplDoublyLinkedList::isEmpty — Checks whether the doubly linked list is empty

说明

public SplDoublyLinkedList::isEmpty ( ) : bool

参数

此函数没有参数。

返回值

Returns whether the doubly linked list is empty.

User Contributed Notes

lincoln dot du dot j at gmail dot com 10-Jul-2017 07:53


//isEmpty is a method of SplDoublyLinkedList 



$obj = new SplDoublyLinkedList();

// Check wither linked list is empty

if ($obj->isEmpty())

{

    $obj->push(2);

    $obj->unshift(10);

}

print_r($obj);



//Output like this

SplDoublyLinkedList Object

(

    [flags:SplDoublyLinkedList:private] => 0

    [dllist:SplDoublyLinkedList:private] => Array

        (

            [0] => 10

            [1] => 2

        )



)