工厂方法模式

A工厂只能创建A产品，B工厂只能创建B产品

意思是：宝马只能造宝马，比亚迪只能造比亚迪

此图为引用，忘记引用哪个博主的了

//产品：A,B产品继承于抽象产品

 class IProduct //抽象 汽车
 {
public:
virtual void show() = 0;
virtual ~IProduct() {}
};

class ProductA : public IProduct //具体产品宝马车
{
public:
    void show() { qDebug()<< "ProductA"; }
};

class ProductB : public IProduct //具体产品比亚迪
{
public:
     void show() { qDebug() << "ProductB";}
};

//工厂：A,B工厂继承于抽象工厂

  class IFactory //抽象工厂
   {
          public:

          virtual ~IFactory() {}

          virtual IProduct* createProduct() = 0;
            };

class FactoryA : public IFactory //宝马工厂
{
public:

    IProduct* createProduct(){    return new ProductA;}
};

class FactoryB : public IFactory //长安工厂
{
public:
    IProduct* createProduct(){    return new ProductB;}
};

怎么调用： 划重点，这里

void main(int argc, char *argv[])
{

   //先创建宝马厂
    IFactory *factory = new FactoryA();

  //宝马厂造一辆宝马车
    IProduct *product = factory->createProduct();
    product->show();

    delete factory;
    delete product;

    //长安工厂造一辆长安
    factory = new FactoryB();
    product = factory->createProduct();
    product->show();
    delete factory;
    delete product;

}