Iterator::key
(PHP 5, PHP 7)
返回当前元素的键
说明
abstract public Iterator::key(void): scalar
返回当前元素的键。
参数
此函数没有参数。
返回值
成功返回标量,失败则返回NULL
。
错误/异常
失败时分发E_NOTICE
级错误。
Since PHP 5.5.X foreach can accept non scalar items. So the return can be anything ;)
And converts everything to integer except string, so in php the post process could be: public function key() { $yourKey = $this->createYourKey(); if (is_object($yourKey) || is_array($yourKey)) throw new Exception('Array and Object not allowed.'); elseif (is_string($yourKey)) return $yourKey; else return (int) $yourKey; }