C65-枚举类型

小秋学嵌入式-不读研版2025-10-14 10:54

枚举类型

枚举类型的定义：

c 复制代码

enum 枚举名 
{
    常量1,
    常量2,
    ...,
    常量n
};

例如:

c 复制代码

enum Weekday 
{
    Monday,
    Tuesday,
    Wednesday,
    Thursday,
    Friday,
    Saturday,
    Sunday
};

枚举类型有以下特点：

枚举常量默认从 0 开始依次递增，如上面的Monday值为 0，Tuesday值为 1，依此类推。

Codes:

c 复制代码

#include <stdio.h>

    //定义枚举类型
enum Weekday
{
    Monday,
    Tuesday,
    Wednesday,
    Thursday,
    Friday,
    Saturday,
    Sunday
};

int main()
{
    //声明枚举变量
    enum Weekday today;
    today=Monday;    //合法赋值
    
    //测试:枚举常量"默认值"
    printf("Monday=%d\n",today);
    today=Sunday;
    printf("Sunday=%d\n",today);

    return 0;
}

Show:

可以显式指定枚举常量的值，例如：

c 复制代码

enum Color 
{
    RED = 1,
    GREEN = 3,
    BLUE = 5
};

Codes:

c 复制代码

#include <stdio.h>

    //定义枚举类型
enum Weekday_1
{
    Monday=3,
    Tuesday,
    Wednesday,
    Thursday,
    Friday,
    Saturday,
    Sunday
};

int main()
{
    //测试:显示指定枚举常量的值
    enum Weekday_1 today1;
    today1=Monday;
    printf("Monday=%d\n",today1);
    today1=Sunday;
    printf("Sunday=%d\n",today1);
    return 0;
}

Show:

未显式指定值的枚举常量，其值为前一个常量的值加 1。

使用枚举类型可以声明变量：

c 复制代码

enum Weekday today;
today = Wednesday;  // 合法赋值

4.枚举类型可以用于比较

Codes:

c 复制代码

#include <stdio.h>

    //定义枚举类型
enum Weekday
{
    Monday,
    Tuesday,
    Wednesday,
    Thursday,
    Friday,
    Saturday,
    Sunday
};

int main()
{
    //声明枚举变量
    enum Weekday today1;
    enum Weekday today2;
    today1=Monday;
    today2=Tuesday;
    if(today1<today2)
    {
        printf("The test was successful.");
    }

    return 0;
}

Show :