学步园

1：枚举里面的值是常量;    例如 enum color {red,orange,yellow};

2：枚举列表中的常量默认为0，1，2等等  例如 enum color {red,orange,yellow};  常量值默认为0，1，2

3:  枚举列表常量值是可以指定的,且指定值后的枚举值将递增   例如enum color {red,orange=10,yellow}; yellow=11

4:  在C语言中枚举可以递增 运算符++,而C++中需要强制转换定义为int再运算符++

 

enum用法例子如下

 

#include<stdio.h>
#include<string.h>
enum  specturm {red,orange,yellow,green,blue,violet};
const char *colors[]={"red","orange","yellow","green","blue","violet"};
#define LEN 30
int main(void)
{
    char choice[LEN];
    int color;
    int  color_is_found=0;
    puts("Enter a color (empty line to quit): ");
    while(gets(choice)!=NULL&&choice[0]!='\0')
    {
        for(color=red;color<=violet;color++)
        {
            if(strcmp(choice,colors[color])==0)
            {
                color_is_found=1;
                break;
            }
        }
        if(color_is_found)
        switch(color)
        {
            case 0:puts("Roses are red");break;
            case 1:puts("Poppies are orange");break;
            case 2:puts("Sunflowers are yellow");break;
            case 3: puts("Grass is green");break;
            case 4:puts("Bluebells are blue");break;
            case 5:puts("Violets are violet");break;
        }
        else printf("I don't know about the color %s.\n",choice);
        color_is_found=0;
        puts("Next color,please(empty line to quit): ");
    }
    puts("Goodbye!");
    return 0;
}