iOS 获取设备的UUID

swift：

class func getUUID() -> String {        let myUUID:CFUUIDRef = CFUUIDCreate(nil)        let UUIDString:CFStringRef = CFUUIDCreateString(nil, myUUID)        let resultString:String = CFStringCreateCopy(nil, UUIDString) as String        print(resultString)        return resultString    }

OC：

-(NSString*) uuid {      CFUUIDRef myUUID = CFUUIDCreate( nil );      CFStringRef uuidString = CFUUIDCreateString( nil, myUUID );      NSString * result = (NSString *)CFStringCreateCopy( NULL, uuidString);      CFRelease(puuid);      CFRelease(uuidString);      return [result autorelease];  }