c++-面向對象：類和對象

類和對象

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <string.h> 


using namespace std;


struct Hero
{
    char name[64];
    int sex;
};

void printHero(struct Hero &h)
{
    cout << "Hero" << endl;

    cout << "name = " << h.name << endl;
    cout << "sex = " << h.sex << endl;
}

class AdvHero
{
public://訪問控制權限
    char name[64];
    int sex;

    void printHero()
    {
        cout << "advHero" << endl;
        cout << "name = " << name << endl;
        cout << "sex = " << sex << endl;
    }
};


class Animal
{
    //{}之內 叫類的內部， 之外叫類的外部
public:
    char kind[64];
    char color[64];

//在public下面定義成員變量和函數 是可以在類的內部和外部均可以訪問的。
    void printAnimal()
    {
        cout << "kind = " << kind << endl;
        cout << "color = " << color << endl;
    }

    void write()
    {
        cout << kind << "開始鞋子了" << endl;
    }
    void run()
    {
        cout << kind << "跑起來了" << endl;
    }

    //
private:
    //在private下面定義的成員變量和方法只可以在類的內部訪問
    
};

int main(void)
{
    Hero h;

    strcpy(h.name, "gailun");
    h.sex = 1;
    printHero(h);



    AdvHero advH;
    strcpy(advH.name, "ChunBro");
    advH.sex = 1;

    advH.printHero();

    cout << "-----------" << endl;
    Animal dog;

    strcpy(dog.kind, "dog");
    strcpy(dog.color, "yellow");

    Animal sheep;

    strcpy(sheep.kind, "sheep");
    strcpy(sheep.color, "white");

    

    dog.write();
    sheep.run();

    return 0;
}

類的封裝

一個類類的內部，默認的訪問控制權限是private

一個結構體默認的訪問控制權限的是public

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>

using namespace std;

struct Date
{
    int year;
    int month;
    int day;
};

void init_date(struct Date & d)
{
    cout << "year, month, day" << endl;
    cin >> d.year;
    cin >> d.month;
    cin >> d.day;
}

//打印data的接口
void print_date(struct Date &d)
{
    cout << d.year << "年" << d.month << "月" << d.day << "日" << endl;
}

bool is_leap_year(struct Date &d)
{
    if (((d.year % 4 == 0) && (d.year % 100 != 0)) || (d.year % 400 == 0)) {
        return true;
    }
    return false;
}

class MyDate
{
public:
    //成員方法 成員函數
    void init_date()
    {
        cout << "year, month, day" << endl;
        cin >> year;
        cin >> month;
        cin >> day;
    }

    //打印data的接口
    void print_date()
    {
        cout << year << "年" << month << "月" << day << "日" << endl;
    }

    bool is_leap_year()
    {
        if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) {
            return true;
        }
        return false;
    }


    int get_year()
    {
        return year;
    }

    void set_year(int new_year)
    {
        year = new_year;
    }

protected://保護控制權限。在類的繼承中跟private有區別，在單個類中，跟private是一抹同樣。
private:
    int year;
    int month;
    int day;
};

//一個類類的內部，默認的訪問控制權限是private
class Hero
{

    int year;
};

//一個結構體默認的訪問控制權限的是public
struct Hero2
{
    int year;
    void print()
    {

    }
};

int main(void)
{
#if 0
    Date d1;

    init_date(d1);
    print_date(d1);
    if (is_leap_year(d1) == true) {
        cout << "是閏年 " << endl;
    }
    else {
        cout << "不是閏年 " << endl;
    }
#endif


    MyDate my_date;

    my_date.init_date();

    my_date.print_date();

    if (my_date.is_leap_year() == true)
    {
        cout << "是閏年 " << endl;
    }
    else {
        cout << "不是閏年 " << endl;
    }

    //getter,setter
    cout << my_date.get_year() << endl;
    my_date.set_year(2000);
    cout << my_date.get_year() << endl;

    Hero h;
    //h.year = 1000;

    Hero2 h2;
    h2.year = 100;

    return 0;
}

面向對象和麪向過程

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>

using namespace std;

class Dog
{
public:
    void eat(char *food)
    {
        cout << name << "³Ô" << food << endl;
    }

    char name[64];
};

//ÃæÏò¹ý³Ì
void eat(class Dog &dog, char *food)
{
    cout << dog.name << "³Ô" << food << endl;
}




int main(void)
{
    Dog dog;

    strcpy(dog.name, "¹·");

    eat(dog, "Ïè");

    dog.eat("Ïè");



    return 0;
}