PHP SplDoublyLinkedList offsetUnset()函数用法示例

SplDoublyLinkedList::offsetUnset()函数是PHP中的内置函数, 用于取消给定索引处的值。
语法如下:

void SplDoublyLinkedList::offsetUnset( $index )

参数:该函数接受单个参数$ index包含要取消设置其值的索引值。
【PHP SplDoublyLinkedList offsetUnset()函数用法示例】返回值:它不返回任何值。
下面的程序说明了SplDoublyLinkedList::offsetUnset()PHP中的功能:
程序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::offsetUnset() function //to unset the value at given index $list -> offsetUnset(0); $list -> offsetUnset(1); $list -> offsetUnset(0); $list -> offsetUnset(1); var_dump( $list ); ?>

输出如下:
object(SplDoublyLinkedList)#1 (2) { ["flags":"SplDoublyLinkedList":private]=> int(0) ["dllist":"SplDoublyLinkedList":private]=> array(1) { [0]=> string(5) "Geeks" } }

程序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::offsetUnset() function //to unset the value at given index $list -> offsetUnset(1); $list -> offsetUnset(2); print_r( $list ); ?>

输出如下:
SplDoublyLinkedList Object ( [flags:SplDoublyLinkedList:private] => 0 [dllist:SplDoublyLinkedList:private] => Array ( [0] => 1 [1] => 3 [2] => 5 ))

参考: https://www.php.net/manual/en/spldoublylinkedlist.offsetunset.php

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