1、main.cpp

#include <iostream>
#include <string>
#include "Shape.h"
#include "circle.h"
#include "rectangle.h"//创建Shape/Circle/Rectangle对象
//用子类对象调用基类函数toString()
using namespace std;
int main() {Shape s1{Color::blue,false};Circle c1{3.9,Color::green,true};Rectangle r1{4.0,1.0,Color::white,true };cout << s1.toString() << endl;cout << c1.toString() << endl;cout << r1.toString() << endl;return 0;
}

2、circle.cpp

#include <iostream>
#include "circle.h"Circle::Circle(){radius = 1.0;
}//使用基类的构造函数初始化基类的数据成员
Circle::Circle(double radius_, Color color_, bool filled_) : Shape{color_,filled_} {radius = radius_;
}double Circle::getArea() {return (3.14 * radius * radius);
}double Circle::getRadius() const {return radius;
}void Circle::setRadius(double radius) {this->radius = radius;
}

3、circle.h

#pragma once
#include "Shape.h"
//补全Circle 类，从shape继承
class Circle : public Shape{double radius;
public:Circle();Circle(double radius_, Color color_, bool filled_);double getArea();double getRadius() const;void setRadius(double radius);
};

4、rectangle.cpp

#include "rectangle.h"
Rectangle::Rectangle(double w, double h, Color color_, bool filled_) :width{ w }, height{h}, Shape{ color_,filled_ } {}double Rectangle::getWidth() const { return width; }
void Rectangle::setWidth(double w) { width = w; }
double Rectangle::getHeight() const { return height; }
void Rectangle::setHeight(double h) { height = h; }double Rectangle::getArea() const { return width * height; }

5、rectangle.h

#pragma once
#include "Shape.h"
//创建rectangle类，从shape继承
class Rectangle : public Shape {
private:double width{1.0};double height{1.0};
public:Rectangle() = default;Rectangle(double w, double h, Color color_, bool filled_);//get函数被声明为const类型，表明这个函数本身不去修改类的私有属性double getWidth() const;void setWidth(double w);double getHeight() const;void setHeight(double h);double getArea() const;
};

6、Shape.h

#pragma once
#include <iostream>
#include <string>
#include <array>
using std::string;
//C++14的字符串字面量
using namespace std::string_literals;
enum class Color {white , black , read , green , blue , yellow,
};class Shape {
private://就地初始化Color color{Color::black};bool filled{false};
public://无参构造函数，强制由编译器生成Shape() = default;Shape(Color color_, bool filled_){color = color_;filled = filled_;}Color getColor() { return color; }void setColor(Color color_) { color = color_; }bool isFilled() { return filled; }void setFilled(bool filled_) {filled = filled_;}string toString() {//自动转化为string类型的对象std::array<string, 6> c{ "white"s,"black"s,"red"s,"green"s,"blue"s,"yellow"s,};return "Shape: " + c[static_cast<int>(color)] + " " + (filled ? "filled"s : "not filled"s);}
};