王老师 结构体 第一讲

一种数据类型,由多个分量构成,共同描述一个对象.

声明语法:

struct 类型名

{

分量类型1 分量名1;

...

分量类型n 分量名n;

};

结构型变量定义: struct 结构类型名 变量名;

分配内存: 按结构定义的顺序,分配各个分量,可能有空白区.

示例函数代码:

#include "stdio.h"

/*
* 结构体:日期类型
*/
struct date
{
int y, m, d;
};

/*
* 结构体:学生
*/
struct student
{
int id;
char name[20];
struct date birthday;
};

/*
* 复数
*/
struct complex
{
int real;
int imaginary;
};

complex add(complex a, complex b)
{
a.imaginary += b.imaginary;
a.real += b.real;
return a;
}

complex add(complex * a, complex * b)
{
a->imaginary += b->imaginary;
a->real += b->real;
return *a;
}

void main()
{
/*
* 测试一下sizeof函数
*/
int x = 3;
printf("%d/n", sizeof(x));
printf("%d/n", sizeof(x = 4));
printf("%d/n", x);

/*
* 使用struct
*/
struct complex a, b, c;
a.real = 1;
a.imaginary = 2;

b.real = 1;
b.imaginary = 3;

c = add(a, b);
printf("%d, %d/n", a.real, a.imaginary);
printf("%d, %d/n", c.real, c.imaginary);

c = add(&a, &b);
printf("%d, %d/n", a.real, a.imaginary);
printf("%d, %d/n", c.real, c.imaginary);
}