C++上机实验报告实验六

实验六多态性1.实验目的1.掌握运算符重载的方法2.学习使用虚函数实现动态多态性2.实验要求1.定义Point类，有坐标_x，_y两个成员变量；对Point类重载“＋＋”(自增)、“――”(自减)运算符，实现对坐标值的改变。2.定义一个车(vehiele)基类，有Run、Stop等成员函数，由此派生出自行车(bicycle)类、汽车(motorcar)类，从bicycle和motorcar派生出摩托车(motorcycle)类，它们都有Run、Stop等成员函数。观察虚函数的作用。3.(选做)对实验4中的People类重载“＝＝”运算符和“=”运算符，“＝＝”运算符判断两个people类对象的id属性是否相等；“=”运算符实现People类对象的赋值操作。3.实验内容及实验步骤1.编写程序定义Point类，在类中定义整型的私有成员变量_x_y，定义成员函数Point&operator++()；Pointoperator++(int)；以实现对Point类重载“++”(自增)运算符，定义成员函数Point＆operator－－()；Pointoperator－－(int)；以实现对Point类重载“－－”(自减)运算符，实现对坐标值的改变。程序名：1ab8_1．cpp。2.编写程序定义一个车(vehicle)基类，有Run、Stop等成员函数，由此派生出自行车(bicycle)类、汽车(motorcar)类，从bicycle和motorcar派生出摩托车(motorcycle)类，它们都有Run、Stop等成员函数。在main()函数中定义vehicle、bicycle、motorcar、motorcycle的对象，调用其Run()、Stop()函数，观察其执行情况。再分别用vehicle类型的指针来调用这几个对象的成员函数，看看能否成功；把Run、Stop定义为虚函数，再试试看。程序名：lab8_2．cpp。4.思考题1.如何将一个运算符重载为类的成员函数？函数类型operator运算符（形参表）{函数体；}2.如何将一个运算符重载为类的友元函数？friend函数类型operator运算符（形参表）{函数体；}3.如何实现运行时刻的多态？在基类的成员函数前加上virtual，就可以在它的派生类中声明相同名字和类型的成员函数，在运行过程中，系统会自动判断并调用相应类中的成员函数，从而在调用过程中实现多态。5.源程序1.lab8_1.cpp#includeiostreamusingnamespacestd;classPoint{private:int_x;int_y;public://构造.析构函数Point(){}Point(int,int);~Point(){}//++.--重载Point&operator++();Pointoperator++(int);Point&operator--();Pointoperator--(int);//输出点坐标voidshowPoint();};Point::Point(intx,inty){_x=x;_y=y;}Point&Point::operator++(){_x++;_y++;return*this;}PointPoint::operator++(int){Pointp=*this;++(*this);returnp;}Point&Point::operator--(){_x--;_y--;return*this;}PointPoint::operator--(int){Pointp=*this;--(*this);returnp;}voidPoint::showPoint(){coutThepointis(_x,_y)endl;}intmain(){Pointapoint(3,5);apoint.showPoint();(apoint++).showPoint();//测试后置++apoint.showPoint();(++apoint).showPoint();//测试前置++apoint.showPoint();(apoint--).showPoint();//测试后置--apoint.showPoint();(--apoint).showPoint();//测试前置--apoint.showPoint();return0;}2.lab8_2.cpp#includeiostreamusingnamespacestd;classVehicle{public://基类的成员函数为虚函数virtualvoidrun(){coutVehicleisrunning!endl;}virtualvoidstop(){coutVehicleisstopping!endl;}};classBicycle:virtualpublicVehicle//按虚基类继承{public:voidrun(){coutBicycleisrunning!endl;}voidstop(){coutBicycleisstopping!endl;}};classMotorcar:virtualpublicVehicle//按虚基类继承{public:voidrun(){coutMotorcarisrunning!endl;}voidstop(){coutMotorcarisstopping!endl;}};classMotorcycle:publicBicycle,publicMotorcar{public:voidrun(){coutMotorcycleisrunning!endl;}voidstop(){coutMotorcycleisstopping!endl;}};intmain(){Vehicleveh;Bicyclebic;Motorcarmot;Motorcyclem;//对象名.函数测试/*veh.run();veh.stop();bic.run();bic.stop();mot.run();mot.stop();m.run();m.stop();*///基类指针测试Vehicle*p;p=&veh;p-run();p-stop();p=&bic;p-run();p-stop();p=&mot;p-run();p-stop();p=&m;p-run();p-stop();return0;}3.lab8_3#includeiostream#includecstringusingnamespacestd;//Date类classDate{private:intyear;intmonth;intday;public:Date();Date(inty,intm,intd);Date(Date&p);~Date();voidsetDate();voidshowDate();};//People类，其中含Date类型的数据classPeople{private:charname[11];charnumber[7];charsex[3];Datebirthday;public:charid[16];People();People(char*n,char*nu,char*s,Dateb,char*i);People(People&p);~People();booloperator==(People&);People&operator=(People&);voidsetName();voidsetNumber();voidsetSex();voidsetId();voidshowPeople();};//Date构造函数Date::Date(){}Date::Date(inty,intm,intd){year=y;month=m;day=d;}Date::Date(Date&p){year=p.year;month=p.month;day=p.day;}//析构inlineDate::~Date(){}//Date成员函数，设置出生年月日voidDate::setDate(){inty,m,d;coutInputtheyear:;ciny;coutInputthemonth:;cinm;coutInputtheday:;cind;year=y;month=m;day=d;}//Date内联成员函数，输出年月日inlinevoidDate::showDate(){coutBirthdayisyear年month月day日endl;}//People构造函数People::People(){};People::People(char*n,char*nu,char*s,Dateb,char*i){strcpy(name,n);strcpy(number,nu);strcpy(sex,s);birthday=b;strcpy(id,i);}People::People(People&p){strcpy(name,p.name);strcpy(number,p.number);birthday=p.birthday;strcpy(id,p.id);}//People析构inlinePeople::~People(){}//People成员函数，设置各类数据voidPeople::setName(){coutPleaseinputtheperson'sname:;cin.getline(name,11,'\n');}voidPeople::setNumber(){coutInputnumber:;cin.getline(number,7,'\n');}voidPeople::setSex(){coutInputsex:;cin.getline(sex,3,'\n');}voidPeople::setId(){coutInputid:;cin.getline(id,16,'\n');}//People内联成员函数，输出人员信息inlinevoidPeople::showPeople(){coutName:nameendl;coutNumber:numberendl;coutSex:sexendl;coutID:idendl;}boolPeople::operator==(People&p){returnid==p.id;}People&People::operator=(People&p){strcpy(name,p.name);strcpy(number,p.number);birthday=p.birthday;strcpy(id,p.id);return*this;}//检测==重载的普通函数voidtest(People&x,People&y){if(strcmp(x.id,y.id)==0){coutTheir'sIDsaresameendl;}else{coutTheir'sIDsaredifferentendl;}}intmain(){/*inti;charspaceA;//生成3个Date类型的对象Datedate[3]={Date(0,0,0),Date(0,0,0),Date(0,0,0)};//生成3个People类型的对象Peopleperson[3]={People(0,0,0,date[0],0),People(0,0,0,date[1],0),People(0,0,0,date[2],0)};//设置这3个对象的各类信息for(i=0;i3;i++){person[i].setName();person[i].setNumber();person[i].setSex();person[i].setId();date[i].setD