PHP SplObjectStorage使用实例

SplObjectStorage是SPL标准库中的数据结构对象容器,用来存储一组对象,特别是当你需要唯一标识对象的时候,需要的朋友可以参考下:

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：

 <?php
 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();
 }