虛函數組實作虛級聯繼承 - 全開放和（接近）全閉合模式

// 全開放模式
// virtualfunctionarrayrealizevirtualcascadederivation.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"

// 進階虛類
class A_layer5
{
protected:
	virtual void f_layer0() = 0;
	virtual void f_layer1() = 0;
	virtual void f_layer2() = 0;
	virtual void f_layer3() = 0;
	virtual void f_layer4() = 0;

protected:
	int i_layer0;
	int i_layer1;
	int i_layer2;
	int i_layer3;
	int i_layer4;
};

// 繼承虛類
class A_layer4 : public A_layer5
{
public:
	void f_layer4() {/*實作四級虛函數功能*/i_layer4 = 4;};
};
class A_layer3 : public A_layer4
{
public:
	void f_layer3() {/*實作三級虛函數功能*/i_layer3 = 3;};
};
class A_layer2 : public A_layer3
{
public:
	void f_layer2() {/*實作二級虛函數功能*/i_layer2 = 2;};
};
class A_layer1 : public A_layer2
{
public:
	void f_layer1() {/*實作一級虛函數功能*/i_layer1 = 1;};
};
class A_layer0 : public A_layer1
{
public:
	void f_layer0() {/*實作零級虛函數（實函數）功能*/i_layer0 = 0;};
};

// 實類
class A : public A_layer0
{
};

int _tmain(int argc, _TCHAR* argv[])
{
	A a;// 實作
	a.f_layer0();
	a.f_layer1();
	a.f_layer2();
	a.f_layer3();
	a.f_layer4();
	return 0;
}

           

// （接近）全閉合模式
// virtualfunctionarrayrealizevirtualcascadederivation.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "stdlib.h"

// 進階虛類
class A_layer5
{
protected:
	virtual int f_layer0() = 0;
	virtual int f_layer1() = 0;
	virtual int f_layer2() = 0;
	virtual int f_layer3() = 0;
	virtual int f_layer4() = 0;
};

// 繼承虛類
class A_layer4 : public A_layer5
{
protected:
	int f_layer4() {/*實作四級虛函數功能*/return rand();};
};
class A_layer3 : public A_layer4
{
protected:
	int f_layer3() {/*實作三級虛函數功能*/return f_layer4();};
};
class A_layer2 : public A_layer3
{
protected:
	int f_layer2() {/*實作二級虛函數功能*/return f_layer3();};
};
class A_layer1 : public A_layer2
{
protected:
	int f_layer1() {/*實作一級虛函數功能*/return f_layer2();};
};
class A_layer0 : public A_layer1
{
public:
	int f_layer0() {/*實作零級虛函數（實函數）功能*/return f_layer1();};
};

// 實類
class A : public A_layer0
{
};

int _tmain(int argc, _TCHAR* argv[])
{
	A a;// 實作
	int secret_number = a.f_layer0();
	return 0;
}