(PHP 7 >= 7.2.0, PHP 8)
ReflectionClass::isIterable — Check whether this class is iterable
Check whether this class is iterable (i.e. can be used inside foreach).
此函数没有参数。
示例 #1 Basic ReflectionClass::isIterable() Usage
<?php
class IteratorClass implements Iterator
{
public function __construct() {}
public function key(): mixed {}
public function current(): mixed {}
public function next(): void {}
public function valid(): bool {}
public function rewind(): void {}
}
class DerivedClass extends IteratorClass {}
class NonIterator {}
function dump_iterable($class)
{
$reflection = new ReflectionClass($class);
var_dump($reflection->isIterable());
}
$classes = ["ArrayObject", "IteratorClass", "DerivedClass", "NonIterator",];
foreach ($classes as $class) {
echo "Is $class iterable? ";
dump_iterable($class);
}
?>以上示例会输出：
Is ArrayObject iterable? bool(true) Is IteratorClass iterable? bool(true) Is DerivedClass iterable? bool(true) Is NonIterator iterable? bool(false)