迭代器模式:
迭代器模式是提供一个顺序访问一个聚合对象中的各个元素,而不暴露对象内部。类似 for foreach。
<?php class TestIterator implements Iterator{ private $array; private $currentIndex = 0; public function __construct(array $array) { $this->array = $array; } /** * 初始化下标 */ function rewind() { echo '初始化下标'.PHP_EOL; $this->currentIndex = count($this->array)-1; } /** * 返回当前数据 */ function current() { echo '下标为'.$this->currentIndex.'的值为:'.PHP_EOL; return $this->array[$this->currentIndex].PHP_EOL; } /** * 索引指向下一个 */ function next(){ --$this->currentIndex; } /** * 返回当前下标 */ function key() { return $this->currentIndex; } /** * 判断是否有下一个元素 */ function valid() { echo '下标为'.$this->currentIndex.'判断是否有值'; return isset($this->array[$this->currentIndex]); } } $list = [1,2,3,4,5,6,7,8,9,10]; $test = new TestIterator($list); foreach($test as $t){ echo $t; }