php框架中常用的设计模式

1.单例模式

  

//单例模式
class Demo
{
    private static $obj;
    
    private function __construct()
    {
        
    }
    
    
    private function __clone()
    {
    
    }
    
    public static function OBJ()
    {
        if(!isset(self::$obj))
        {
            self::$obj = new self;
        }
        return self::$obj;
    }
            
}

2.工厂模式

//简单工厂模式
//抽象方法
abstract  class  operation
{
    abstract public function getValue($one,$two);
}

//jia  fa  lei
class operationAdd extends operation
{
    public function getValue($one, $two)
    {
        return $one + $two;    
    }
}

class operationSub extends operation
{
    public function getValue($one, $two)
    {
        return $one - $two;    
    }
}

class factory
{
    public static function getObject($name)
    {
        switch($name){
        case '+': return new operationAdd(); break;
        case '-': return new operationSub(); break;
        default: 
            break;    
        
        }
    }

}



$demo = factory::getObject('+');
$value = $demo->getValue(2,1);
echo $value;

3.注册器模式（把每次new的对象放到一个静态数组中）

4. 观察者模式

   把每个需要通知的类，实例化后的对象交给观察者类中的静态数组保存，然后调用观察者类的方法，方法的作用是便利静态数组，调用每个对象中的通知方法

　

<?php
//guan cha zhe lei
class Server
{
    private static $objList = array();

    public function add($obj)
    {
        self::$objList[] = $obj;    
    }
    
    public function notify()
    {
        foreach(self::$objList as $obj)
        {
            $obj->notify();    
        }    
    }
}

abstract class client
{
    abstract public function notify();
}

class one extends client
{
    public function notify()
    {
        echo "one<br>";    
    }
}

class two extends client
{
    public function notify()
    {
        echo "two<br>";    
    }
}


$server = new Server(); 

$one = new one();
$two = new two();

$server->add($one);
$server->add($two);

$server->notify();