Generator::key
(PHP 5 >= 5.5.0, PHP 7, PHP 8)
Generator::key — 返回当前产生的键
参数
此函数没有参数。
返回值
返回当前产生的键。
范例
示例 #1 Generator::key() example
<?php
function Gen()
{
yield 'key' => 'value';
}
$gen = Gen();
echo "{$gen->key()} => {$gen->current()}";
以上例程会输出:
key => value
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User Contributed Notes 1 note
jasonrlester at yahoo dot com ¶
16 days ago
This is important when considering how other Generators work such as JavaScript's an Python's. While PHP's generator has the ->valid() method they don't, or an equivalent. JS uses Iterator protocol which says next() should return an object of
{
done: bool,
value: mixed
}
In which case you can use keys->done to see if the generator can still be iterated.