在PHP源码中,你可能会看到各种设计模式的应用。设计模式是软件开发中的一种通用的、可重用的解决方案,用于解决在软件设计中经常遇到的问题。以下是一些在PHP源码中常见的设计模式及其解析:
class Singleton {
private static $instance;
private function __construct() {}
public static function getInstance() {
if (null === self::$instance) {
self::$instance = new Singleton();
}
return self::$instance;
}
}
interface Product {
public function getProductType();
}
class ProductA implements Product {
public function getProductType() {
return "Product A";
}
}
class ProductB implements Product {
public function getProductType() {
return "Product B";
}
}
class Factory {
public static function createProduct($type) {
switch ($type) {
case 'A':
return new ProductA();
case 'B':
return new ProductB();
default:
throw new InvalidArgumentException("Invalid product type.");
}
}
}
interface Observer {
public function update($data);
}
class ConcreteObserverA implements Observer {
public function update($data) {
echo "ConcreteObserverA received data: " . $data . "\n";
}
}
class ConcreteObserverB implements Observer {
public function update($data) {
echo "ConcreteObserverB received data: " . $data . "\n";
}
}
class Subject {
private $observers = [];
public function attach(Observer $observer) {
$this->observers[] = $observer;
}
public function detach(Observer $observer) {
$key = array_search($observer, $this->observers);
if ($key !== false) {
unset($this->observers[$key]);
}
}
public function notify($data) {
foreach ($this->observers as $observer) {
$observer->update($data);
}
}
}
interface Target {
public function request();
}
class Adaptee {
public function specificRequest() {
return "Specific request.";
}
}
class Adapter implements Target {
private $adaptee;
public function __construct(Adaptee $adaptee) {
$this->adaptee = $adaptee;
}
public function request() {
return $this->adaptee->specificRequest();
}
}
这些设计模式在PHP源码中的应用可以帮助你更好地理解代码结构和设计思想。当然,还有很多其他设计模式,如桥接模式、组合模式、装饰器模式等,它们在实际编程中也有广泛的应用。