构造函数与析构函数研究

首先先贴代码

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#include <iostream>
using namespace std;
class A
{
public:
A() { cout << "class A is constructed" << endl;}
~A() { cout << "class A is destroyed" << endl; }
//method
void fa() { cout << "class A fa method" << endl;}
void fb() { cout << "class A fb method" << endl;}
};
class B : public A
{
public:
B() { cout << "class B is constructed" << endl;}
~B() { cout << "class B is destroyed" << endl; }
//method
void fa() { cout << "class B fa method" << endl;}
void fb() { cout << "class B fb method" << endl;}
};
int main()
{
A *pa = new A;
B *pb = new B;
cout << endl;
pa->fa();
pa->fb();
cout << endl;
pb->fa();
pb->fb();
cout << endl;
delete pa;
delete pb;
cout << endl;
return 0;
}
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运行结果如下:
class A is constructed
class A is constructed
class B is constructed
class A fa method
class A fb method
class B fa method
class B fb method
class A is destroyed
class B is destroyed
class A is destroyed

细心的娃肯定能发下些问题了,在子类的构造函数中先构造父类然后在构造子类,析构时先析构子类然后再析构父累

PS:这个题上次去Foxit有考,刚开始我是这么想的,后来居然给改了,郁闷阿………..

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