c++ 匿名枚举

来源：互联网发布：北京奥运会门票知乎编辑：程序博客网时间：2024/05/29 14:36

匿名枚举

enum { value = 0 , value2 = 1};
enum { value3 = 2};

刚看到时候有些奇怪，经过考察，他的功能等价于静态常成员变量，

struct IsCustomUnsignedInt 
{ 
    enum { value = 0 , value2 = 1}; 
    enum { value3 = 2};  
    static const int value4 = 3; 
    static int value5; 
};   
int IsCustomUnsignedInt::value5 = 4;
void main() 
{       
    int result = IsCustomUnsignedInt::value;
    int result2 = IsCustomUnsignedInt::value2; 
    IsCustomUnsignedInt::value3 = 3; //error C2440: '=' : cannot convert from 'int' to '' 
    //IsCustomUnsignedInt::value4 = 4; //error C3892: 'value4' : you cannot assign to a variable that is const 
    IsCustomUnsignedInt::value5 = 5;      
}

写了一个更一般的例子，果然。

enum Type{First,Second,Third}; 
struct TestEnum { 
   enum Type2{One,Two,Three}; 
   void Test() 
    { 
         int i = One; 
    }
}; 
void main() 
{ 
    int i = First;
    TestEnum test; 
    test.Test(); 
    //int x = One; //error 
     int j = TestEnum::One; 
}

如果有不对请指出，共同学习进步哦！thx