【C++ Primer 第15章】定义派生类析构函数

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• 基类和派生类析构函数执行顺序

定义派生类析构函数

【注意】定义一个对象时先调用基类的构造函数、然后调用派生类的构造函数；析构的时候恰好相反：先调用派生类的析构函数、然后调用基类的析构函数。

#include <iostream>
using namespace std;

class Base
{
public:
    Base()
    {
        cout << "Base contruction" << endl;
    }
    virtual ~Base()
    {
        cout << "Base deconstruction" << endl;
    }

};

class Derived : public Base
{
public:
    Derived(int i)
    {
        num = i;
        cout << "Derived contruction " << num << endl;
    }
    virtual ~Derived()
    {
        cout << "Derived deconstruction" << num << endl;
    }
private:
    int num;
};

int main()
{
    Derived derived(1);

    Base* basePtr;
    basePtr = new Derived(2);
    delete basePtr;
}

输出结果：