Microsoft设计模式理论是,"该文档引入模式,然后将它们呈现在存储库或目录中,其组织有助于找到解决问题的正确模式组合".
一个类有一个实例,它提供了一个全局访问点,下面的代码将解释关于单身概念.
<?php class Singleton { public static function getInstance() { static $instance = null; if (null === $instance) { $instance = new static(); } return $instance; } protected function __construct() { } private function __clone() { } private function __wakeup() { } } class SingletonChild extends Singleton { } $obj = Singleton::getInstance(); var_dump($obj === Singleton::getInstance()); $anotherObj = SingletonChild::getInstance(); var_dump($anotherObj === Singleton::getInstance()); var_dump($anotherObj === SingletonChild::getInstance()); ?>
基于静态方法创建实现的上述示例是getInstance()
A Class Simple创建对象并且您想要使用该对象,下面的示例将解释工厂设计模式.
<?php class Automobile { private $bikeMake; private $bikeModel; public function __construct($make, $model) { $this->bikeMake = $make; $this->bikeModel = $model; } public function getMakeAndModel() { return $this->bikeMake . ' ' . $this->bikeModel; } } class AutomobileFactory { public static function create($make, $model) { return new Automobile($make, $model); } } $pulsar = AutomobileFactory::create('ktm', 'Pulsar'); print_r($pulsar->getMakeAndModel()); class Automobile { private $bikeMake; private $bikeModel; public function __construct($make, $model) { $this->bikeMake = $make; $this->bikeModel = $model; } public function getMakeAndModel() { return $this->bikeMake . ' ' . $this->bikeModel; } } class AutomobileFactory { public static function create($make, $model) { return new Automobile($make, $model); } } t$pulsar = AutomobileFactory::create('ktm', 'pulsar'); print_r($pulsar->getMakeAndModel()); ?>
工厂模式的主要困难是它会增加复杂性,对于优秀的程序员来说这是不可靠的.
策略模式生成一个族算法并封装每个算法.这里的每个算法都应该在系列内互换.
<?php $elements = array( array( 'id' => 2, 'date' => '2011-01-01', ), array( 'id' => 1, 'date' => '2011-02-01' ) ); $collection = new ObjectCollection($elements); $collection->setComparator(new IdComparator()); $collection->sort(); echo "Sorted by ID:\n"; print_r($collection->elements); $collection->setComparator(new DateComparator()); $collection->sort(); echo "Sorted by date:\n"; print_r($collection->elements); ?>
视图充当GUI,模型充当后端,控制充当适配器.这里三个部分相互连接.它将传递数据并相互访问数据.