在设计模式中,PHP实例通常用于实现单例模式、工厂模式和原型模式等。
class Singleton
{
private static $instance;
private function __construct() {}
public static function getInstance()
{
if (self::$instance === null) {
self::$instance = new Singleton();
}
return self::$instance;
}
}
$singleton = Singleton::getInstance();
interface Shape
{
public function draw();
}
class Circle implements Shape
{
public function draw()
{
echo "Drawing Circle";
}
}
class Square implements Shape
{
public function draw()
{
echo "Drawing Square";
}
}
class ShapeFactory
{
public function createShape($type)
{
if ($type === 'circle') {
return new Circle();
} elseif ($type === 'square') {
return new Square();
}
return null;
}
}
$factory = new ShapeFactory();
$circle = $factory->createShape('circle');
$circle->draw();
class Prototype
{
private $name;
public function __construct($name)
{
$this->name = $name;
}
public function clone()
{
return clone $this;
}
}
$prototype = new Prototype('Object');
$clone = $prototype->clone();