枚舉增強(qiáng)程序的可讀性，用法上還是需要注意的
1.C語言的寫法
enum XMPPReconnectFlags
{
kShouldReconnect = 1 << 0, // If set, disconnection was accidental, and autoReconnect may be used
kMultipleChanges = 1 << 1, // If set, there have been reachability changes during a connection attempt
kManuallyStarted = 1 << 2, // If set, we were started manually via manualStart method
kQueryingDelegates = 1 << 3, // If set, we are awaiting response(s) from the delegate(s)
};
或者是
typedef enum XMPPReconnectFlags
{
kShouldReconnect = 1 << 0, // If set, disconnection was accidental, and autoReconnect may be used
kMultipleChanges = 1 << 1, // If set, there have been reachability changes during a connection attempt
kManuallyStarted = 1 << 2, // If set, we were started manually via manualStart method
kQueryingDelegates = 1 << 3, // If set, we are awaiting response(s) from the delegate(s)
}XMPPReconnectFlags;//此處的XMPPReconnectFlags為別名
2.OC的寫法
typedef NS_ENUM(NSInteger, XMPPMessageBodyType) {
XMPPMessageBodyTypeText = 1, //文本
XMPPMessageBodyTypeImage, //圖片
XMPPMessageBodyTypeSound, //語音
XMPPMessageBodyTypeMap, //地理信息（文本）
XMPPMessageBodyTypeNotification, //通知
XMPPMessageBodyTypeCustom, //自定義
XMPPMessageBodyTypeVideo, //視頻
XMPPMessageBodyTypeExpression, //表情
};
第一個(gè)枚舉值只要NSInteger類型各薇，后面的依次累加，中間再重新賦值，后面的會從賦值處重新累加
3.NS_ENUM和NS_OPTIONS
NS_ENUM和NS_OPTIONS本質(zhì)是一樣的隧枫，僅僅從字面上來區(qū)分其用途喉磁。NS_ENUM是通用情況，NS_OPTIONS一般用來定義具有位移操作或特點(diǎn)的情況
typedef NS_OPTIONS(NSInteger, ShareViewItemType) {
ShareViewItemTypeWX = 1,
ShareViewItemTypeWXFC = 1 << 0,
ShareViewItemTypeQQ= 1 << 1,
ShareViewItemTypeWB= 1 << 1,
ShareViewItemTypeReport= 1 << 3,
ShareViewItemTypeBarrage = 1 << 4,
ShareViewItemTypeAll = 1 << 5,
};
如果多選枚舉官脓，那么需要這樣判斷
+ (instancetype)shareViewWithDic:(NSDictionary*)dic shareViewItemType:(ShareViewItemType)shareViewItemType;
{
if (shareViewItemType == (ShareViewItemTypeWX|ShareViewItemTypeWXFC)) {
// code
}
}
4.官方的全選枚舉
<code>UIControl</code>的枚舉
typedef NS_OPTIONS(NSUInteger, UIControlEvents) {
UIControlEventTouchDown = 1 << 0, // on all touch downs
UIControlEventTouchDownRepeat = 1 << 1, // on multiple touchdowns (tap count > 1)
UIControlEventTouchDragInside = 1 << 2,
UIControlEventTouchDragOutside = 1 << 3,
UIControlEventTouchDragEnter = 1 << 4,
UIControlEventTouchDragExit = 1 << 5,
UIControlEventTouchUpInside = 1 << 6,
UIControlEventTouchUpOutside = 1 << 7,
UIControlEventTouchCancel = 1 << 8,
UIControlEventValueChanged = 1 << 12, // sliders, etc.
UIControlEventPrimaryActionTriggered NS_ENUM_AVAILABLE_IOS(9_0) = 1 << 13, // semantic action: for buttons, etc.
UIControlEventEditingDidBegin = 1 << 16, // UITextField
UIControlEventEditingChanged = 1 << 17,
UIControlEventEditingDidEnd = 1 << 18,
UIControlEventEditingDidEndOnExit = 1 << 19, // 'return key' ending editing
UIControlEventAllTouchEvents = 0x00000FFF, // for touch events
UIControlEventAllEditingEvents = 0x000F0000, // for UITextField
UIControlEventApplicationReserved = 0x0F000000, // range available for application use
UIControlEventSystemReserved = 0xF0000000, // range reserved for internal framework use
UIControlEventAllEvents = 0xFFFFFFFF
};
最后一個(gè)<code> UIControlEventAllEvents </code>賦值為0xFFFFFFFF协怒，意為全選，實(shí)際工程使用沒有問題确买，很方便斤讥，但是在
Archive的時(shí)候會報(bào)錯(cuò)
屏幕快照 2016-06-29 下午12.28.10.png
這個(gè)地方需要這樣改
typedef NS_OPTIONS(NSUInteger, ShareViewItemType) {
ShareViewItemTypeWX = 1,
ShareViewItemTypeWXFC = 1 << 0,
ShareViewItemTypeQQ= 1 << 1,
ShareViewItemTypeWB= 1 << 1,
ShareViewItemTypeReport= 1 << 3,
ShareViewItemTypeBarrage = 1 << 4,
ShareViewItemTypeAll = 0xFFFFFFFF,
};
你可以這樣判斷條件
+ (instancetype)shareViewWithDic:(NSDictionary*)dic shareViewItemType:(ShareViewItemType)shareViewItemType;
{
// 入?yún)hareViewItemType為ShareViewItemTypeAll
if (shareViewItemType & ShareViewItemTypeBarrage) {
// code
}
}
