PHP SplObjectStorage使用实例

PHP SPL SplObjectStorage是用来存储一组对象的，特别是当你需要唯一标识对象的时候。

PHP SPL SplObjectStorage类实现了Countable,Iterator,Serializable,ArrayAccess四个接口。可实现统计、迭代、序列化、数组式访问等功能。

看下面一个简单的例子：

class A {

public $i;

public function __construct($i) {

$this->i = $i;

}

}

$a1 = new A(1);

$a2 = new A(2);

$a3 = new A(3);

$a4 = new A(4);

$container = new SplObjectStorage();

//SplObjectStorage::attach 添加对象到Storage中

$container->attach($a1);

$container->attach($a2);

$container->attach($a3);

//SplObjectStorage::detach 将对象从Storage中移除

$container->detach($a2);

//SplObjectStorage::contains用于检查对象是否存在Storage中

var_dump($container->contains($a1)); //true

var_dump($container->contains($a4)); //false

//遍历

$container->rewind();

while($container->valid()) {

var_dump($container->current());

$container->next();

}