c++类的引入

 

1.    输出一个人的姓名和年龄

#include <stdio.h>



int main(int argc, char **argv)

{

        char *zs_name = "zhangsan";

        int zs_age = 10;



        char *ls_name = "lisi";

        int ls_age = 16;



        printf("name = %s, age = %d\n", zs_name, zs_age);

        printf("name = %s, age = %d\n", ls_name, ls_age);



        return 0;

}

2.   输出多个人的工作和年龄

#include <stdio.h>



int main(int argc, char **argv)

{

        char *names[] = {"zhangsan", "lisi"};

        char ages[] = {10, 16};

        char *work[] = {"teacher", "doctor"};



        int i;



        for (i = 0; i < 2; i++)

        {

                printf("name = %s, age = %d\n", names[i], ages[i]);

        }



        return 0;

}

3.   输出多个人多项信息，引入结构体

#include <stdio.h>



struct person {

        char *name;

        int age;

        char *work;



        void (*printInfo)(struct person *per);

};



int main(int argc, char **argv)

{

        struct person persons[] = {

                {"zhangsan", 10, "teacher"},

                {"lisi", 16, "doctor"},

        };





        int i;



        for (i = 0; i < 2; i++)

        {

                printf("name = %s, age = %d, work = %s\n", persons[i].name, persons[i].age, persons[i].work);

        }



        return 0;

}

 

4.   结构体内定义函数，在c语言内只能写函数指针

#include <stdio.h>



struct person {

        char *name;

        int age;

        char *work;



        void (*printInfo)(struct person *per);

};



void printInfo(struct person *per)

{

        printf("name = %s, age = %d, work = %s\n", per->name, per->age, per->work);

}

int main(int argc, char **argv)

{

        struct person persons[] = {

                {"zhangsan", 10, "teacher", printInfo},

                {"lisi", 16, "doctor", printInfo},

        };



        persons[0].printInfo(&persons[0]);

        persons[1].printInfo(&persons[1]);



        return 0;

}

5.   另存为cpp文件，直接在结构体里面写上函数

#include <stdio.h>

struct person {
        char *name;
        int age;
        char *work;

        void printInfo(void)
        {
                printf("name = %s, age = %d, work = %s\n", name, age, work);
        }
};

int main(int argc, char **argv)
{
        struct person persons[] = {
                {"zhangsan", 10, "teacher"},
                {"lisi", 16, "doctor"},
        };

        persons[0].printInfo();
        persons[1].printInfo();

        return 0;
}

C++对struct做了两个扩展

1.       可以在结构体里面直接写函数

2.       函数可以直接访问结构体里面的属性

由此引出class。

#include <stdio.h>

class person {
public:
        char *name;
        int age;
        char *work;

        void printInfo(void)
        {
                printf("name = %s, age = %d, work = %s\n", name, age, work);
        }
};

int main(int argc, char **argv)
{
        struct person persons[] = {
                {"zhangsan", 10, "teacher"},
                {"lisi", 16, "doctor"},
        };

        persons[0].printInfo();
        persons[1].printInfo();

        return 0;
}

 

6.  面向对象三大特性：封装，继承，多态。

 

 

 

转载于:https://my.oschina.net/u/3659800/blog/1529010