这样也可以，为什么要用IteratorIterator 呢？

Question

<?php //OuterIterator.php

$array = ['value1','value2','value3','value4'];

$outerObj = new OuterImpl(new ArrayIterator($array));

foreach ($outerObj as $key => $value){

echo "++".$key."---".$value."<br />";

}

class OuterImpl extends ArrayIterator

{

public function current(){

return parent::current()."_tail";

}

public function key(){

return "Pre_".parent::key();

}

?>

Answer 1

两者迭代器不一致你尝试下 laravel 的自带的Collection和ORM 的arrayCollection 就明白了底层不一致，很多结果都不一致