c++ - 了解 C++ 析构函数在派生类中的行为

Question

我正在阅读 Stroustrup 的 C++ 编程书中的一段代码。

class Vector_container : public Container {
    Vector v;
public:    
    // Vector_container implements Container
    Vector_container(int s) : v(s) { } // Vector of s elements
    ~Vector_container() {}

    double& operator[](int i) { return v[i]; }
    int size() const { return v.size(); }    
};

作者接着说

1. The destructor (~Vector_container()) overrides the base class destructor (~Container()).
2. Note that the member destructor (~Vector()) is implicitly invoked by its class’s destructor (~Vector_container()).

关于 #1，为什么覆盖发生在不同名称的函数中？

关于 #2，类的析构函数系统地调用成员析构函数是否是 C++ 的一个特性？

Answer 1

如果您不添加析构函数，编译器会创建一个析构函数。在你的情况下你有一个，所以编译器不会生成一个。

是的，成员和基类在类的析构函数被调用后被析构。来自 cppreference.com :

For both user-defined or implicitly-defined destructors, after the body of the destructor is executed, the compiler calls the destructors for all non-static non-variant members of the class, in reverse order of declaration, then it calls the destructors of all direct non-virtual base classes in reverse order of construction (which in turn call the destructors of their members and their base classes, etc), and then, if this object is of most-derived class, it calls the destructors of all virtual bases.