字符串与枚举相互转换

enum DPodRecordType{  

     DPodRecordTypeA = 0,  

     DPodRecordTypeCNAME,  

     DPodRecordTypeMX,  

     DPodRecordTypeTXT,  

     DPodRecordTypeNS,  

     DPodRecordTypeAAAA,  

     DPodRecordTypeSRV,  

    DPodRecordTypeURL  

 };  

 typedef enum DPodRecordType DPodRecordType;  

 const NSArray *___DPodRecordType;  

 // 创建初始化函数。等于用宏创建一个getter函数  

 #define cDPodRecordTypeGet (___DPodRecordType == nil ? ___DPodRecordType = [[NSArray alloc] initWithObjects:  

   @"A",  

  @"CNAME",  

  @"MX",  

   @"TXT",  

   @"NS",  

   @"AAAA",  

  @"SRV",  

 @"URL", nil] : ___DPodRecordType)  

 // 枚举 to 字串  

 #define cDPodRecordTypeString(type) ([cDPodRecordTypeGet objectAtIndex:type])  

// 字串 to 枚举  

 #define cDPodRecordTypeEnum(string) ([cDPodRecordTypeGet indexOfObject:string])