虚析构函数分析，为啥第一个输出是9，第二个输出是2呢
虚析构函数分析，为什么第一个输出是9，第二个输出是2呢？
有人可以帮我分析一下，下面的代码，为什么第一个输出结果是9，第二个输出结果会是2呢？
------解决方案--------------------
因为调用了两次析构，资料详解：
http://blog.****.net/kevinzhangyang/article/details/6638479
因为都是从A派生过来的，你在A的析构里面设置为了2所以是2
------解决方案--------------------
http://dev.yesky.com/145/2206145.shtml
------解决方案--------------------
add copy constructor, made it more clear:
有人可以帮我分析一下，下面的代码，为什么第一个输出结果是9，第二个输出结果会是2呢？
#include <iostream.h>
static int x;
class A
{
public:
A(){ cout<<"AA1"<<endl; x = 1; }
virtual ~A(){ cout<<"~A2"<<endl; x = 2; }
virtual void foo(){ cout<<"A::foo()A3"<<endl; x = 3;}
};
class B : public A
{
public:
B(){ cout<<"BB4"<<endl; x = 4; }
virtual ~B(){ cout<<"~B5"<<endl; x = 5; }
void foo(){ cout<<"B::foo()B6"<<endl; x = 6; }
void bar(){ cout<<"B::bar()"<<endl; foo(); }
};
class C : public B
{
public:
C(){ cout<<"CC7"<<endl;x = 7; }
virtual ~C(){ cout<<"~C8"<<endl; x = 8; }
void foo(){ cout<<"C::foo()C9"<<endl; x = 9 ;}
void bar(){ cout<<"C::bar()"<<endl; foo(); }
};
int main(void)
{
C testc;
testc.foo();
cout<<"1------------------------------------ "<< x<<endl;
((C)testc).foo();
cout<<"2------------------------------------ "<< x<<endl;
}
------解决方案--------------------
因为调用了两次析构，资料详解：
http://blog.****.net/kevinzhangyang/article/details/6638479
因为都是从A派生过来的，你在A的析构里面设置为了2所以是2
------解决方案--------------------
http://dev.yesky.com/145/2206145.shtml
------解决方案--------------------
add copy constructor, made it more clear:
static int x;
class A
{
public:
A()
{
cout<<"AA1"<<endl;
x = 1;
}
A(const A& a)
{
cout << "A copy constructor loaded" << endl;
*this = a;
x = 11;
}
virtual ~A()
{
cout<<"~A2"<<endl;
x = 2;
}
virtual void foo()
{
cout<<"A::foo()A3"<<endl;
x = 3;
}
};
class B : public A
{
public:
B()
{
cout<<"BB4"<<endl;
x = 4;
}
B(const B& b)
{
cout << "B copy constructor loaded" << endl;
*this = b;
x = 12;
}
virtual ~B()
{
cout<<"~B5"<<endl;
x = 5;
}
void foo()
{
cout<<"B::foo()B6"<<endl;
x = 6;
}
void bar()
{
cout<<"B::bar()"<<endl;
foo();
}
};
class C : public B
{
public:
C()
{
cout<<"CC7"<<endl;
x = 7;
}
C(const C& c)
{
cout << "C copy constructor loaded" << endl;
*this = c;
x = 13;
}
virtual ~C()
{
cout<<"~C8"<<endl;
x = 8;
}
void foo()
{
cout<<"C::foo()C9"<<endl;