在C中使用枚舉

Question

我有這個枚舉：

  enum Seasons{
  winter,spring,summer,autumn
  };

該代碼將做什么？

 enum Seasons curr_season;
 curr_season = autumn;
 curr_season = 19;

謝謝！

Answer 1

enum Seasons{
    winter,spring,summer,autumn
};

上面創建了以下內容

winter=0, spring=1, summer=2 and autumn=3

注意： enums只是整數！ ..也可以取負數！

enum Seasons curr_season;
curr_season = autumn;
/* curr_season will now have 3 assigned */

curr_season = 19;
/* curr_season will now have 19 assigned */

您可以運行以下代碼進行檢查！

#include <stdio.h>

enum Seasons{
        winter,spring,summer,autumn
};

void print_seanons(void)
{
    printf("winter = %d \n", winter);
    printf("spring = %d \n", spring);
    printf("summer = %d \n", summer);
    printf("autumn = %d \n", autumn);
    return;
}

int main(void)
{
    enum Seasons curr_season;
    print_seanons();

    curr_season = autumn;
    printf("curr_season = %d \n", curr_season);
    curr_season = 19; 
    printf("curr_season = %d \n", curr_season);
    return 0;

}

Answer 2

枚舉常量在c中的類型為int 。 盡管enum並非顯式為int類型，但枚舉類型和int之間的轉換是靜默的。 通常沒有對枚舉的約束檢查，因此您的代碼在功能上等效於：

int curr_season;
curr_season = 3;
curr_season = 19;

Answer 3

枚舉是整數值，因此它將為curr_season分配值19。

交叉使用（將整數值分配給枚舉）被認為是不良的編程習慣，應避免使用。