The LimitIterator class

(PHP 5 >= 5.1.0, PHP 7, PHP 8)

简介

LimitIterator类允许遍历一个 Iterator 的限定子集的元素.

类摘要

LimitIterator extends IteratorIterator implements OuterIterator {
/* 方法 */
public current ( ) : mixed
public getInnerIterator ( ) : Iterator
public getPosition ( ) : int
public key ( ) : mixed
public next ( ) : void
public rewind ( ) : void
public seek ( int $offset ) : int
public valid ( ) : bool
}

范例

Example #1 LimitIterator usage example

<?php

// Create an iterator to be limited
$fruits = new ArrayIterator(array(
    'apple',
    'banana',
    'cherry',
    'damson',
    'elderberry'
));

// Loop over first three fruits only
foreach (new LimitIterator($fruits, 0, 3) as $fruit) {
    var_dump($fruit);
}

echo "\n";

// Loop from third fruit until the end
// Note: offset starts from zero for apple
foreach (new LimitIterator($fruits, 2) as $fruit) {
    var_dump($fruit);
}

?>

以上例程会输出：

string(5) "apple"
string(6) "banana"
string(6) "cherry"

string(6) "cherry"
string(6) "damson"
string(10) "elderberry"

Table of Contents

User Contributed Notes

christophg at grenz-bonn dot de 15-Jul-2021 11:21
If the inner iterator implements SeekableIterator, LimitIterator uses seek() after rewind() to move to the offset.
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