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(PHP 5 >= 5.1.0, PHP 7, PHP 8)
AppendIterator::__construct — Constructs an AppendIterator
Constructs an AppendIterator.
此函数没有参数。
示例 #1 Iterating AppendIterator with foreach
<?php
$pizzas = new ArrayIterator(array('Margarita', 'Siciliana', 'Hawaii'));
$toppings = new ArrayIterator(array('Cheese', 'Anchovies', 'Olives', 'Pineapple', 'Ham'));
$appendIterator = new AppendIterator;
$appendIterator->append($pizzas);
$appendIterator->append($toppings);
foreach ($appendIterator as $key => $item) {
echo $key . ' => ' . $item . PHP_EOL;
}
?>
以上示例会输出:
0 => Margarita 1 => Siciliana 2 => Hawaii 0 => Cheese 1 => Anchovies 2 => Olives 3 => Pineapple 4 => Ham
示例 #2 Iterating AppendIterator with the AppendIterator API
<?php
$pizzas = new ArrayIterator(array('Margarita', 'Siciliana', 'Hawaii'));
$toppings = new ArrayIterator(array('Cheese', 'Anchovies', 'Olives', 'Pineapple', 'Ham'));
$appendIterator = new AppendIterator;
$appendIterator->append($pizzas);
$appendIterator->append($toppings);
while ($appendIterator->valid()) {
printf(
'%s => %s => %s%s',
$appendIterator->getIteratorIndex(),
$appendIterator->key(),
$appendIterator->current(),
PHP_EOL
);
$appendIterator->next();
}
?>
以上示例会输出:
0 => 0 => Margarita 0 => 1 => Siciliana 0 => 2 => Hawaii 1 => 0 => Cheese 1 => 1 => Anchovies 1 => 2 => Olives 1 => 3 => Pineapple 1 => 4 => Ham
When using iterator_to_array() to copy the values of the AppendIterator
into an array, you have to set the optional use_key
argument to
false
. When use_key
is not false
any keys reoccurring in inner
iterators will get overwritten in the returned array. There is no way to preserve the original keys.