C++聚合关系类的构造函数的调用顺序

1 #pragma once
2 class Engine
3 {
4 public:
5     Engine();
6     ~Engine();
7 };

 1 #include <iostream>
 2 #include "Engine.h"
 3 using namespace std;
 4 
 5 Engine::Engine()
 6 {
 7     cout << "调用构造函数:Engine()" << endl;
 8 }
 9 
10 Engine::~Engine()
11 {
12     cout << "调用析构函数:~Engine()" << endl;
13 }

 1 #pragma once
 2 #include "Engine.h"
 3 
 4 class Car
 5 {
 6 public:
 7     Car();
 8     ~Car();
 9 private:
10     Engine m_eCar;
11 };

 1 #include <iostream>
 2 #include "Car.h"
 3 using namespace std;
 4 
 5 Car::Car()
 6 {
 7     cout << "调用构造函数:Car()" << endl;
 8 }
 9 
10 Car::~Car()
11 {
12     cout << "调用析构函数:~Car()" << endl;
13 }