什么是簡單工廠模式

簡單工廠模式又被稱為靜態工廠方法模式(Static Factory Method)
具體就是通過這個工廠類的方法來創建對象

```
<?php
abstract class Product 
{
    abstract function play();
}

class A extends Product
{
    public function play()
    {
        echo 'I play CS:GO';
    }
}

class B extends Product
{
    public function play()
    {
        echo 'I am playing LOL';
    }
}

class SimpleFactory
{
    static function create($name)
    {
        switch($name) {
            case 'cs':
                return new A();
                break;
            case 'lol':
                return new B();
                break;
            default:
                break;
        }
    }
}

$obj_1 = SimpleFactory::create('cs');
$obj_1->play(); // I play CS:GO
$obj_2 = SimpleFactory::create('lol');
$obj_2->play(); // I am playing LOL