PHP常见设计模式

• 简单工厂

<?php# 简单工厂abstract class mycoach{public function __construct(){}}class cultivatecpc extends mycoach{public function __construct(){echo "把陈培昌培养为搏击教练"."\n";}}class cultivatecj extends mycoach{public function __construct(){echo "把程劲培养为搏击教练"."\n";}}class martialclub {public function cultivate($name){switch($name){case 'cj':return new cultivatecj();case 'cpc':return new cultivatecpc();default:echo '培养一个小教练'."\n";break;}return null;}}class clubmaster{public function cultivate(){$myclub = new martialclub();$myclub->cultivate('cj');$myclub = new martialclub();$myclub->cultivate('cpc');}}$mymaster = new clubmaster();$mymaster->cultivate();

输出结果：

把程劲培养为搏击教练
把陈培昌培养为搏击教练

•  （复杂）工厂

<?php
abstract class mycoach
{public function __construct(){}
}class cpc extends mycoach
{public function __construct(){echo "培养出了搏击教练昌仔"."\n";}
}class cj extends mycoach
{public function __construct(){echo "培养出了搏击教练劲儿弟弟"."\n";  }
}interface cultivate{function cultivate();
}class cultivatecpc implements cultivate
{public function cultivate(){return new cpc();}
}class cultivatecj implements cultivate
{public function cultivate(){return new cj();}
}class coach{public function __construct(){$coach = new cultivatecpc();$coach->cultivate();$coach = new cultivatecj();$coach->cultivate();}
}$littlecoach = new coach();

输出结果：

培养出了搏击教练昌仔
培养出了搏击教练劲儿弟弟

•  观察者模式

<?phpclass watcher{private $name;public function __construct($myname){$this->name=$myname;}public function update($food){switch($food){case '奶油蛋糕':echo $food."上桌了，".$this->name.'取出了一份纸盘子和塑料叉子,切了一块'."\n";break;case '烤鸭':echo $food."上桌了，".$this->name.'取了张薄饼，夹了些许葱丝，刷了些甜面酱'."\n";break;default:echo $food."上桌了，".$this->name."赶紧加了两筷子"."\n";break;}return null;}}class watchee{private $watchlist = [];public function addwatcher($watcher){$this->watchlist[]=$watcher;}public function removewatcher($watcher){$target = array_search($watcher,$this->watchlist);$target = (int)$target;unset($this->watchlist[$target]);//echo $target."\n";
     }public function loaddish($dishname){$this->notify($dishname);}public  function  notify($dishname){

　　　　　　#这里推荐用foreach循环，for循环带来的陷阱是，如果以数字为索引，执行removewatcher方法后，有些索引就没了，访问不到就会报错

　　　　foreach($this->watchlist as $k=>$v){$this->watchlist[$k]->update($dishname);}}}$cpc = new watcher('陈培昌');$cj = new watcher('程劲');$observee = new watchee();$observee->addwatcher($cpc);$observee->addwatcher($cj);$observee->loaddish('葱香四川凉面');$observee->removewatcher($cj);$observee->loaddish('奶油蛋糕');$xxd = new watcher('徐晓冬');$observee->addwatcher($xxd);$observee->loaddish('避风塘茄子');

输出结果：

葱香四川凉面上桌了，陈培昌赶紧加了两筷子
葱香四川凉面上桌了，程劲赶紧加了两筷子
奶油蛋糕上桌了，陈培昌取出了一份纸盘子和塑料叉子,切了一块
避风塘茄子上桌了，陈培昌赶紧加了两筷子
避风塘茄子上桌了，徐晓冬赶紧加了两筷子