PHP design patterns iterator pattern

The iterator pattern traverses the internal elements of an aggregate object without knowing the internal implementation. Compared with traditional programming patterns, the iterator pattern can hide the operations required to traverse elements.

AllHacl.php

<?<span>php

namespace Baobab;


</span><span>class</span> AllHacl <span>implements</span><span> \iterator{

    </span><span>protected</span><span>$ids</span><span>;</span><span>protected</span><span>$index</span>;<span>//</span><span>当前位置</span><span>function</span><span> __construct(){
        </span><span>$db</span> = Factory::getDatabase('ha_cl'<span>);
        </span><span>$result</span> = <span>$db</span>->query('select ID from ha_cl'<span>);
        </span><span>$this</span>->ids = <span>$result</span>-><span>fetch_all(MYSQLI_ASSOC);
    }<br><span>/*<span>*<br>　　 * 返回当前元素<br><span>*/</span></span></span></span><span>function</span><span>current</span><span>(){
        </span><span>$id</span> = <span>$this</span>->ids[<span>$this</span>->index]['ID'<span>];
        </span><span>return</span> Factory::getHacl(<span>$id</span><span>);
   }<br><span><span>/*<span>*<br>　　 * 向前移动到下一个元素<br><span>*/</span></span></span></span></span><span>function</span><span>next</span><span>(){
        </span><span>$this</span>->index ++<span>;
    }

    </span><span>/*</span><span>*
     * 返回到迭代器的第一个元素
     </span><span>*/</span><span>function</span><span>rewind</span><span>(){
        </span><span>$this</span>->index = 0<span>;
    }

    </span><span>/*</span><span>*
     * 查询当前位置是否有数据
     </span><span>*/</span><span>function</span><span> valid(){
        </span><span>return</span><span>$this</span>->index - <span>count</span>(<span>$this</span>-><span>ids);
    }<br><span><span>/*<span>*<br>　　 * 返回当前元素的键<br><span>*/</span></span></span></span></span><span>function</span><span>key</span><span>(){
        </span><span>return</span><span>$this</span>-><span>index;
    }
}</span>

index.php

<span>$hacls</span> = <span>new</span><span> \Baobab\AllHacl();
</span><span>foreach</span>(<span>$hacls</span><span>as</span><span>$hacl</span><span>){
    </span><span>var_dump</span>(<span>$hacl</span>-><span>haclname);
}</span>

Hacl class related content refer to the data object mapping mode. http://www.cnblogs.com/tianxintian22/p/5232016.html

The above has introduced the PHP design pattern iterator pattern, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.