组合模式

 1 <?php
 2 
 3 interface Renderable
 4 {
 5     public function render();
 6 }
 7 
 8 
 9 class Form implements Renderable
10 {
11     private $elements;
12 
13     /**
14      * runs through all elements and calls render() on them, then returns the complete representation
15      * of the form.
16      *
17      * from the outside, one will not see this and the form will act like a single object instance
18      *
19      * @return string
20      */
21     public function render()
22     {
23         $formCode = ‘‘;
24 
25         foreach ($this->elements as $e) {
26             $formCode .= $e->render();
27         }
28 
29         return $formCode;
30     }
31 
32     public function addElement(\Renderable $element)
33     {
34         $this->elements[spl_object_hash($element)] = $element;
35     }
36 
37     public function removeElement(\Renderable $element)
38     {
39         unset($this->elements[spl_object_hash($element)]);
40     }
41 }
42 
43 class InputElement implements Renderable
44 {
45     private $_name;
46 
47     public function __construct($name)
48     {
49         $this->_name = $name;
50     }
51 
52     public function render()
53     {
54         return "<input name=‘".$this->_name."‘ placeholder=‘Please input your name‘ />";
55     }
56 }
57 
58 class TextElement implements Renderable
59 {
60     private $_name;
61 
62     public function __construct($name)
63     {
64         $this->_name = $name;
65     }
66 
67     public function render()
68     {
69         return "<textarea cols=‘5‘ rows=‘3‘ name=‘".$this->_name."‘></textarea>";
70     }
71 }
72 
73 
74 
75 $form = new Form();
76 $input = new InputElement(‘name‘);
77 $text = new TextElement(‘text‘);
78 
79 $form->addElement($input);
80 $form->addElement($text);
81 
82 $embed  = new Form();
83 $embed->addElement($input);
84 $embed->addElement($text);
85 
86 $form->addElement($embed);
87 
88 
89 print htmlspecialchars($form->render());