基类和派生类：构造函数和析构函数的执行顺序

在Visual Studio中，新建控制台工程，构造类如下：

#include<iostream>
using namespace std;

class CBase {
public:
CBase() {
cout << "CBase():Constructor" << endl;
}
~CBase() {
cout << "CBase(): Destructor" << endl;
}
};

class CDerive :public CBase {
public:
CDerive() {
cout << "CDerive():Constructor" << endl;
}
~CDerive() {
cout << "CDerive(): Destructor" << endl;
}
};

对应不同的指针进行 delete 操作，结果如下：

(i)

int main(int argc, char* argv[])
{
CBase* p = new CDerive();
delete p;
return 0;
}

运行结果：

S:\ComputerTech\VS2015\Release>Test.exe
CBase():Constructor
CDerive():Constructor
CBase(): Destructor

(ii)

int main(int argc, char* argv[])
{
CDerive* pp = new CDerive();
delete pp;
return 0;
}

运行结果：

S:\ComputerTech\VS2015\Release>Test.exe
CBase():Constructor
CDerive():Constructor
CDerive(): Destructor
CBase(): Destructor

(iii)

int main(int argc, char* argv[])
{
CDerive* pp = new CDerive();
CBase * p = (CBase*)pp;
delete p;
return 0;
}

运行结果：

S:\ComputerTech\VS2015\Release>Test.exe
CBase():Constructor
CDerive():Constructor
CBase(): Destructor

(iv)

int main(int argc, char* argv[])
{
CBase * p = new CDerive();
CDerive * pp = (CDerive*)p;
delete pp;
return 0;
}

运行结果：

S:\ComputerTech\VS2015\Release>Test.exe
CBase():Constructor
CDerive():Constructor
CDerive(): Destructor
CBase(): Destructor