设计模式----工厂模式-简单工厂模式

下面通过手机生产的过程进行理解：

#include <stdio.h>

typedef enum productType
{
    xiaomi,
    iphone,
    huawei
}PRODUCTTYPE;
class Phone
{
public:
    virtual void MakePhone() = 0;
};
class MI : public Phone
{
public:
    void MakePhone()
    {
        printf("make xiaomi phone\n");
    }
};
class IPHONE : public Phone
{
public:
    void MakePhone()
    {
        printf("make iphone phone\n");
    }
};
class HUAWEI : public Phone
{
public:
    void MakePhone()
    {
        printf("make huawei phone\n");
    }
};
class SimpleFactory
{
public:
    Phone *createPhone(PRODUCTTYPE type)
    {
        switch (type)
        {
        case xiaomi:
           return new MI();
        case iphone:
           return new IPHONE();
        case huawei:
           return new HUAWEI();
        default:
           return NULL;
        }
    }
};
int main()
{
    SimpleFactory *factory = new  SimpleFactory();
    Phone *phone1 =  factory->createPhone(huawei);
    if (phone1 != NULL)
        phone1->MakePhone();
    Phone *phone2 =  factory->createPhone(xiaomi);
    if (phone2 != NULL)
        phone2->MakePhone();
    Phone *phone3 =  factory->createPhone(iphone);
    if (phone3 != NULL)
        phone3->MakePhone();
    delete phone1;
    phone1 = NULL;
    delete phone2;
    phone2 = NULL;
    delete phone3;
    phone3 = NULL;
    return 0;
}