AppendIterator::key
(PHP 5 >= 5.1.0, PHP 7, PHP 8)
AppendIterator::key — Gets the current key
說明
public AppendIterator::key(): scalar
Get the current key.
參數
此函式沒有參數。
返回值
The current key if it is valid or null otherwise.
範例
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;
}
?>
以上例程會輸出：
a aardwolf b bear c capybara 0 apple 1 orange 2 lemon a aardwolf b bear c capybara 0 apple 1 orange 2 lemon
參見
- Iterator::key() - 返回目前元素的鍵
- AppendIterator::current() - Gets the current value
- AppendIterator::valid() - Checks validity of the current element
- AppendIterator::next() - Moves to the next element
- AppendIterator::rewind() - Rewinds the Iterator