(PHP 5 >= 5.1.0, PHP 7, PHP 8)
AppendIterator::key — Gets the current key
Get the current key.
此函数没有参数。
The current key if it is valid or null otherwise.
示例 #1 AppendIterator::key() basic example
<?php
$array_a = new ArrayIterator(array('a' => 'aardwolf', 'b' => 'bear', 'c' => 'capybara'));
$array_b = new ArrayIterator(array('apple', 'orange', 'lemon'));
$iterator = new AppendIterator;
$iterator->append($array_a);
$iterator->append($array_b);
// Manual iteration
$iterator->rewind();
while ($iterator->valid()) {
echo $iterator->key() . ' ' . $iterator->current() . PHP_EOL;
$iterator->next();
}
echo PHP_EOL;
// With foreach
foreach ($iterator as $key => $current) {
echo $key . ' ' . $current . PHP_EOL;
}
?>以上示例会输出：
a aardwolf b bear c capybara 0 apple 1 orange 2 lemon a aardwolf b bear c capybara 0 apple 1 orange 2 lemon