SplDoublyLinkedList::offsetUnset()

(PHP 5 >= 5.3.0, PHP 7)

Unsets the value at the specified $index

说明

publicSplDoublyLinkedList::offsetUnset(mixed $index) : void

Unsets the value at the specified index.

参数

$index

The index being unset.

返回值

没有返回值。

错误／异常

ThrowsOutOfRangeExceptionwhen$indexis out of bounds or when$indexcannot be parsed as an integer.

When unsetting an offset, the element will be removed from the double linked list. So the following code:
<?php
$obj = new SplDoublyLinkedList();
$obj->push(4);
$obj->push(5);
$obj->push(6);
$obj->offsetUnset(1);
echo "Our Linked List:";
print_r($obj);
?>
Will output:
Our Linked List:SplDoublyLinkedList Object
(
  [flags:SplDoublyLinkedList:private] => 0
  [dllist:SplDoublyLinkedList:private] => Array
    (
      [0] => 4
      [1] => 5
      [2] => 6
    )
)
Our New Linked List:SplDoublyLinkedList Object
(
  [flags:SplDoublyLinkedList:private] => 0
  [dllist:SplDoublyLinkedList:private] => Array
    (
      [0] => 4
      [1] => 6
    )
Notice that the element with the index 2 has now the index 1. The original element with index 1 did not only had it's value unset but was also removed from the list.