黑马程序员技术交流社区

标题: typedef NS_OPTIONS(NSUInteger, NSCalendarOptions) [打印本页]

---

作者: u37kl    时间: 2016-2-18 14:51
标题: typedef NS_OPTIONS(NSUInteger, NSCalendarOptions)
typedef NS_OPTIONS(NSUInteger, NSCalendarOptions) {
    NSCalendarWrapComponents = (1UL << 0), // option for arithmetic operations that do calendar addition
   
    NSCalendarMatchStrictly    NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 1),
    NSCalendarSearchBackwards  NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 2),
   
    NSCalendarMatchPreviousTimePreservingSmallerUnits NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 8),
    NSCalendarMatchNextTimePreservingSmallerUnits     NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 9),
    NSCalendarMatchNextTime                           NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 10),
   
    NSCalendarMatchFirst  NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 12),
    NSCalendarMatchLast   NS_ENUM_AVAILABLE(10_9, 7_0) = (1ULL << 13)
};  // 这是枚举吗？ 位枚举也是这样写吗

---

欢迎光临 黑马程序员技术交流社区 (http://bbs.itheima.com/)

黑马程序员IT技术论坛 X3.2