[RUNOOB]C++继承

REF：

http://www.runoob.com/cplusplus/cpp-inheritance.html

 

一、基类和派生类

程序：

#include "stdafx.h"
#include <iostream>
//#include <string>
//#include <vector>
//#include <cctype>
//#include <cstring>

//using std::string;
//using std::vector;
//using std::isalpha;
//using std::cin;
using std::cout;
using std::endl;
using namespace std;

//基类
class Shape
{
public:
	void setWidth(int w)
	{
		width = w;
	}

	void setHeight(int h)
	{
		height = h;
	}

protected:
	int width;
	int height;
};

//派生类
class Rectangle :public Shape 
{
public:
	int getArea()
	{
		return (width*height);
	}

};

int main(void)
{
	Rectangle Rect;

	Rect.setWidth(5);
	Rect.setHeight(7);

	//输出对象面积
	cout << "Total area:" << Rect.getArea() << endl;

	return 0;
}

执行结果：

二、访问控制和继承

三、继承类型

四、多继承

C++ 类可以从多个类继承成员

程序：

#include <iostream>
 
using namespace std;
 
// 基类 Shape
class Shape 
{
   public:
      void setWidth(int w)
      {
         width = w;
      }
      void setHeight(int h)
      {
         height = h;
      }
   protected:
      int width;
      int height;
};
 
// 基类 PaintCost
class PaintCost 
{
   public:
      int getCost(int area)
      {
         return area * 70;
      }
};
 
// 派生类
class Rectangle: public Shape, public PaintCost
{
   public:
      int getArea()
      { 
         return (width * height); 
      }
};
 
int main(void)
{
   Rectangle Rect;
   int area;
 
   Rect.setWidth(5);
   Rect.setHeight(7);
 
   area = Rect.getArea();
   
   // 输出对象的面积
   cout << "Total area: " << Rect.getArea() << endl;
 
   // 输出总花费
   cout << "Total paint cost: $" << Rect.getCost(area) << endl;
 
   return 0;
}

执行结果：

Total area: 35
Total paint cost: $2450