深入探討C++父類子類中虛函數(shù)的應(yīng)用
構(gòu)造函數(shù)不能是虛函數(shù),因為在調(diào)用構(gòu)造函數(shù)創(chuàng)建對象時,構(gòu)造函數(shù)必須是確定的,所以構(gòu)造函數(shù)不能是虛函數(shù)。
析構(gòu)函數(shù)可以是虛函數(shù)。
1.父類Father.h:
#pragma once
class Father
{
public:
Father(void);
virtual ~Father(void);
virtual int getCount();
public:
int count;
};
Father.cpp
#include "StdAfx.h"
#include "Father.h"
#include <iostream>
using namespace std;
Father::Father(void)
{
count = 1;
cout<<"Father is called. count = "<<count<<endl;
}
Father::~Father(void)
{
cout<<"~Father is called."<<endl;
}
int Father::getCount()
{
cout<<"Father::getCount() count = "<<count<<endl;
return count;
}
2.子類Child.h:
#pragma once
#include "father.h"
class Child :
public Father
{
public:
Child(void);
virtual ~Child(void);
virtual int getCount();
int getAge();
public:
int age;
};
Child.cpp
#include "StdAfx.h"
#include "Child.h"
#include <iostream>
using namespace std;
Child::Child(void)
{
count = 2;
age = 20;
cout<<"Child is called. count = "<<count<<", age = "<<age<<endl;
}
Child::~Child(void)
{
cout<<"~Child is called."<<endl;
}
int Child::getCount()
{
cout<<"Child::getCount() count = "<<count<<endl;
return count;
}
int Child::getAge()
{
cout<<"Child::getAge() age = "<<age<<endl;
return age;
}
3.測試類Test.cpp
#include "stdafx.h"
#include <cstdlib>
#include <iostream>
#include "Child.h"
using namespace std;
int _tmain(int argc, _TCHAR* argv[])
{
Father *father1 = new Father();
cout<<"father1 count = "<<father1->getCount()<<endl;
delete father1;
cout<<"************** father1 end *****************"<<endl<<endl;
Father *father2 = new Child();
cout<<"father2 count = "<<father2->getCount()<<endl; // father2 don't have getAge() method
delete father2;
cout<<"************** father2 end *****************"<<endl<<endl;
Child *child = new Child();
cout<<"child count = "<<child->getCount()<<endl;
cout<<"child age = "<<child->getAge()<<endl;
delete child;
cout<<"************** child end *****************"<<endl<<endl;
getchar();
return 0;
}
4.輸出結(jié)果:
Father is called. count = 1
Father::getCount() count = 1
father1 count = 1
~Father is called.
************** father1 end *****************
Father is called. count = 1
Child is called. count = 2, age = 20
Child::getCount() count = 2
father2 count = 2
~Child is called.
~Father is called.
************** father2 end *****************
Father is called. count = 1
Child is called. count = 2, age = 20
Child::getCount() count = 2
child count = 2
Child::getAge() age = 20
child age = 20
~Child is called.
~Father is called.
************** child end *****************
欄 目:C語言
下一篇:使用map實現(xiàn)單詞轉(zhuǎn)換的實例分析
本文標(biāo)題:深入探討C++父類子類中虛函數(shù)的應(yīng)用
本文地址:http://mengdiqiu.com.cn/a1/Cyuyan/4433.html
您可能感興趣的文章
- 04-02c語言沒有round函數(shù) round c語言
- 01-10深入理解約瑟夫環(huán)的數(shù)學(xué)優(yōu)化方法
- 01-10深入二叉樹兩個結(jié)點的最低共同父結(jié)點的詳解
- 01-10深入理解C++中常見的關(guān)鍵字含義
- 01-10使用C++實現(xiàn)全排列算法的方法詳解
- 01-10深入Main函數(shù)中的參數(shù)argc,argv的使用詳解
- 01-10深入第K大數(shù)問題以及算法概要的詳解
- 01-10深入解析最長公共子串
- 01-10c++中inline的用法分析
- 01-10深入理解鏈表的各類操作詳解


閱讀排行
本欄相關(guān)
- 04-02c語言函數(shù)調(diào)用后清空內(nèi)存 c語言調(diào)用
- 04-02func函數(shù)+在C語言 func函數(shù)在c語言中
- 04-02c語言的正則匹配函數(shù) c語言正則表達
- 04-02c語言用函數(shù)寫分段 用c語言表示分段
- 04-02c語言中對數(shù)函數(shù)的表達式 c語言中對
- 04-02c語言編寫函數(shù)冒泡排序 c語言冒泡排
- 04-02c語言沒有round函數(shù) round c語言
- 04-02c語言分段函數(shù)怎么求 用c語言求分段
- 04-02C語言中怎么打出三角函數(shù) c語言中怎
- 04-02c語言調(diào)用函數(shù)求fibo C語言調(diào)用函數(shù)求
隨機閱讀
- 01-10C#中split用法實例總結(jié)
- 08-05dedecms(織夢)副欄目數(shù)量限制代碼修改
- 01-11Mac OSX 打開原生自帶讀寫NTFS功能(圖文
- 08-05織夢dedecms什么時候用欄目交叉功能?
- 08-05DEDE織夢data目錄下的sessions文件夾有什
- 01-10使用C語言求解撲克牌的順子及n個骰子
- 04-02jquery與jsp,用jquery
- 01-10delphi制作wav文件的方法
- 01-10SublimeText編譯C開發(fā)環(huán)境設(shè)置
- 01-11ajax實現(xiàn)頁面的局部加載