类作为对象成员

#include <iostream>
#include <string>
using namespace std;
//汽车类
class Car
{
public:
    Car();
    Car(string name)
    {
        cout << "Car带参构造函数" << endl;
        mName = name;
    }
    ~Car();

public:
    string mName;
};

Car::Car()
{
    cout << "Car默认构造函数" << endl;
    mName = "特斯拉";
}

Car::~Car()
{
    cout << "Car析构函数" << endl;
}
//拖拉机
class Tractor
{
public:
    Tractor()
    {
        cout << "Tractor默认构造函数" << endl;
        mName = "丰田拖拉机";
    }
    Tractor(string name)
    {
        cout << "Tractor带参数构造函数" << endl;
        mName = name;
    }
    ~Tractor()
    {
        cout << "Tractor析构函数" << endl;
    }
public:
    string mName;
};
//人类
class Person
{
public:
#if 0
    //类mCar不存早合适的构造函数
    Person(string name)
    {
        mName = name;
    }
#else
    //初始化列表可以指定调用构造函数
    Person(string carName, string tracName, string name) :mTractor(tracName), mCar(carName), mName(name)
    {
        cout << "Person构造函数" << endl;
    }
#endif
    void GoWorkByCar()
    {
        cout << mName << "开着" << mCar.mName << "去上班" << endl;
    }
    void GoWorkByTractor()
    {
        cout << mName << "开着" << mTractor.mName << "去上班" << endl;
    }
    ~Person()
    {
        cout << "Person 析构函数" << endl;
    }
private:
    string mName;
    Car mCar;
    Tractor mTractor;
};
int main()
{
    //Person person("张三");
    Person person("宝马", "奔驰拖拉机", "赵四");
    person.GoWorkByCar();
    person.GoWorkByTractor();
}