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A classe LimitIterator

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

Introdução

A classe LimitIterator permite a iteração sobre um subconjunto limitado de itens em um Iterator.

Resumo da classe

class LimitIterator extends IteratorIterator {
/* Métodos */
public __construct(Iterator $iterator, int $offset = 0, int $limit = -1)
public current(): mixed
public getPosition(): int
public key(): mixed
public next(): void
public rewind(): void
public seek(int $offset): int
public valid(): bool
/* Métodos herdados */
}

Exemplos

Exemplo #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);
}

?>

O exemplo acima produzirá:

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

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

Índice

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User Contributed Notes 1 note

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1
christophg at grenz-bonn dot de
2 years ago
If the inner iterator implements SeekableIterator, LimitIterator uses seek() after rewind() to move to the offset.
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