[php]php设计模式 Interator (迭代器模式)

<?php
 2 /**
 3  * 迭代器模式
 4  *
 5  * 提供一个方法顺序访问一聚合对象中的各个元素,而又不暴露对象的内部表示
 6 */
 7 interface Interator
 8 {
 9 publicfunctionnext();
10 publicfunction first();
11 publicfunctioncurrent();
12 publicfunction isDone();
13 }
14 
15 class SomeInterator implements Interator
16 {
17 private$_arr=array();
18 
19 publicfunction __construct($arr)
20     {
21 $this->_arr =$arr;
22     }
23 
24 publicfunction first()
25     {
26 return$this->_arr[0];
27     }
28 
29 publicfunctioncurrent()
30     {
31 returncurrent($this->_arr);
32     }
33 
34 publicfunctionnext()
35     {
36 returnnext($this->_arr);
37     }
38 
39 publicfunction isDone()
40     {
41     }
42 }
43 
44 $objSomeInterator=new SomeInterator(array(1,2,3,4,6,7));
45 echo$objSomeInterator->first(),"<br/>";
46 echo$objSomeInterator->next(),"<br/>";
47 echo$objSomeInterator->current(),"<br/>";
48 echo$objSomeInterator->current(),"<br/>";
49 echo$objSomeInterator->next(),"<br/>";
50 echo$objSomeInterator->current(),"<br/>";