简单工厂模式一般用来构造一系列相同类型的产品,用基类提供接口,具体产品继承基类,工厂函数根据枚举生成不同产品,并返回基类指针

下面是一个简单工厂模式的例子,我们有一个基类car,car可以派生出小米su7,特斯拉,M7等具体型号的产品,创建一个工厂类factory,我们只需要告诉工厂需要的具体型号,工厂负责生产好产品并返回给我们基类指针

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#include <iostream>

enum class model {
su7,
modelY,
M7
};

class car {
public:
virtual void info() = 0;
virtual ~car(){};
};

class MiSu7 : public car{
public:
void info() override {
std::cout << "a su7 car" << std::endl;
}
};

class TeslaModelY : public car {
public:
void info() override {
std::cout << "a ModelY car" << std::endl;
}
};

class AITOM7 : public car {
public:
void info() override {
std::cout << "a M7 car" << std::endl;
}
};

class factory{
public:
car* createCar(model m) {
switch (m) {
case model::su7:
return new MiSu7();
case model::modelY:
return new TeslaModelY();
case model::M7:
return new AITOM7();
}
}
};

int main() {
factory f;

car *mycar = f.createCar(model::modelY);
mycar->info();

delete mycar;
return 0;
}