1.__get __set

class  Test {    private $arr = array(        'x'=>null,        'y'=>null    );    function __get($property) {        if(array_key_exists($property,$this->arr)) {            return $this->arr[$property];        } else {            print "error:can not read this property is not exist other than x or y\n";        }    }    function __set($property,$value) {        if(array_key_exists($property,$this->arr)) {            $this->arr[$property] = $value;        } else {            print "error:can not write this property is not exist other than x or y\n";        }    }}$cl = new Test();$cl->x = 1;echo $cl->x;$cl->t = 2;echo $cl->t;

//结果是1error:can not write this property is not exist other than x or y error:can not read this property is not exist other than x or y

2.__call 函数使用

class HelloWorld {    function display($time) {        for($i=0;$i<$time;$i++) {            print "hello world\n";        }    }}class callHelloWorld {    private $obj;    function __construct() {        $this->obj = new HelloWorld();    }    function __call($method,$arg) {        return call_user_func_array(array($this->obj,$method),$arg);    }}$me = new callHelloWorld();$me->display(3);

结果是

hello world hello world hello world

3.迭代器

class numberSquare implements Iterator {    private $start;    private $end;    private $cur;    public function __construct($start, $end) {        $this->start = $start;        $this->end = $end;    }    public function rewind() {        $this->cur = $this->start;    }    public function key() {        return $this->cur;    }    public function current() {        return pow($this->cur,3);    }    public function next() {        $this->cur++;    }    public function valid() {        return $this->cur <= $this->end;    }}$obj = new numberSquare(2,5);foreach($obj as $key => $value) {    print "the square of $key is $value 
\n";}

结果是

the square of 2 is 8 the square of 3 is 27 the square of 4 is 64 the square of 5 is 125

4.工厂模式

//定义抽象类 user类   读权限给，修改，删除权限不给abstract class User {    private $name = null;    function __construct($name) {        $this->name = $name ;    }    function getName() {        return $this->name;    }    //权限方法    function hasReadPermission() {        return true;    }    function hasModifyPermission() {        return false;    }    function hasDeletePermission() {        return false;    }    //定制方法    function wantsFlsahInterFace() {        return true;    }}class GuestUser extends User {}class CustomerUser extends User {    //customer 有修改权限    function hasModifyPermission() {        return true ;    }}

class AdminUser extends User {    function hasModifyPermission() {        return true ;    }    function hasDeletePermission() {        return true ;    }    function wantsFlsahInterFace() {        return false;    }}class UserFactory {    private static $users = array(        "andy"=>'Admin',        "tom"=>'customer',        "jack"=>'guest'    );    static function create($name) {          switch(self::$users[$name]) {            case 'Admin' :                return new AdminUser($name);                  break;            case 'customer' :                return new CustomerUser($name);                break;            case 'guest' :                return new GuestUser($name);                break;            default:                break;          }    }}

function boolToString($b) {    if($b == true) {        return "yes";    } else {        return "no";    }}function displayPermission( $obj) {        print $obj->getName() . "'s permission:\n";        print "Read: " . boolToString($obj->hasReadPermission());        print "Modify: " . boolToString($obj->hasModifyPermission());        print "Delete: " . boolToString($obj->hasDeletePermission());}function displayRequirement( $obj) {    if($obj->wantsFlsahInterFace()) {        print $obj->getName() . "require flash\n";    }}$login = array("andy",'str','jack');foreach($login as $key =>$val) {    displayPermission(UserFactory::create($val));}

结果是

received updated received updated//实例化时不会有任何输出，直到有一个事件或者一个参数被设置才有所行动，一开始有一个观察类。实现类继承观察类，实现类里面有改变值的类在初始化的时候实例一下。当有值改变时调用实现类继承观察类的方法（即完成通知）方法里面可以写被通知之后的操作，如打印字符串等等

5.观察者模式

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