简单工厂模式

代码示例：

//产品抽象基类
abstract class ApptEncoder
{
	abstract public function encode();
}
//产品子类1
class BloggsApptEncoder extends ApptEncoder
{
	public function encode()
	{
		return "Appointment data encode in BloggsCal format
";
	}
}
//产品子类2
class MegaApptEncoder extends ApptEncoder
{
	public function encode()
	{
		return "Appointment data encode in MegaCal format
";
	}
}

//创建者
class CommsManager
{
	public function getApptEncoder($type)
	{
		switch($type)
		{
			case 'Bloggs':
				return new BloggsApptEncoder();
			case 'Mega':
				return new MegaApptEncoder();
		}
		
	}
}

$manager = new CommsManager();
//生成产品子类1对象
$encoder1 = $manager->getApptEncoder('Bloggs');
echo $encoder1->encode();
//生成产品子类2对象
$encoder2 = $manager->getApptEncoder('Mega');
echo $encoder2->encode();