foreach
(
$it
as
$key
=>
$value
) {
echo
'输出键值:';
var_dump(
$key
,
$value
);
//echo $key;
echo
"\n";
}
程序运行输出:
代码如下
:
string(18) "myIterator::rewind"
string(17) "myIterator::valid"
string(19) "myIterator::current"
string(15) "myIterator::key"
输出键值:
int(0)
string(13) "first_element"
string(16) "myIterator::next"
string(17) "myIterator::valid"
string(19) "myIterator::current"
string(15) "myIterator::key"
输出键值:
int(1)
string(14) "second_element"
string(16) "myIterator::next"
string(17) "myIterator::valid"
string(19) "myIterator::current"
string(15) "myIterator::key"
输出键值:
int(2)
string(12) "last_element"
string(16) "myIterator::next"
string(17) "myIterator::valid"
一般的迭代器内部需要下面的方法:
Iterator::current — Return the current element 返回当前元素
Iterator::key — Return the key of the current element 返回当前元素的键
Iterator::next — Move forward to next element 移向下一个元素
Iterator::
rewind
—
Rewind
the Iterator to the first element 重新回到第一个元素
Iterator::valid — Checks
if
current position is valid 检查当前位置的有效性
如果不是很清楚迭代器的内容工作流程,可以查看下面的迭代器对数组的遍历过程:
代码如下
:
/**