Unity/iOS 中单利的设计模式

Unity 中单利的写法

public class Singleton {private static Singleton _Instace = null;public static Singleton GetInstance(){if (_Instace == null) {_Instace = new Singleton ();}return _Instace;}}

iOS中单利的写法

+ (instancetype)shareTotalDownloader{staticTotalDownloader*total =nil; static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{total = [[TotalDownloaderalloc]init]; });return total;}