我有一个在
Swift中扩展String的枚举类型.
当我尝试使用开关时出现错误：
Case label in a switch should have at least one executable statement
这是我的代码：
enum UserInfosKey:String {
case CameraMyPhotoStream = "CMPS"
case CameraICloudActivated = "CICA"
case CameraICloudShare = "CICS"
case ProjectTodayExtension = "PTE"
case ProjectShareExtension = "PSE"
case NetworkConnection = "NC"
case PhoneLanguage = "PL"
case CameraPhotosCount = "CPC"
case UserIdentifier = "UI"
case VersionHistory = "VH"
case Path = "Path"
}
class UserInfosController: NSObject {
func update(key:UserInfosKey,value:String,context:UserDefaultsMainKeys) -> String {
switch key {
case .CameraICloudActivated:
case .CameraICloudShare:
case .CameraMyPhotoStream:
case .CameraPhotosCount:
case .NetworkConnection:
case .PhoneLanguage:
case .UserIdentifier:
return value
default:
return ""
}
}
}
我很确定这是一个简单的错误,有人看到了吗？
解决方法
swift switch语句中没有隐含的漏洞,因此您必须明确设置：
case .CameraICloudActivated: fallthrough
case .CameraICloudShare: fallthrough
case .CameraMyPhotoStream: fallthrough
case .CameraPhotosCount: fallthrough
case .NetworkConnection: fallthrough
case .PhoneLanguage: fallthrough
case .UserIdentifier:
return value
没有它,每个案例都有隐含的突破.
请注意,swift要求每个switch case包含至少一个语句 – 如果没有语句,则必须使用显式中断(在这种情况下意味着“什么都不做”)