public static OldSingleton Instance() { if (_instance == null) { _instance = new OldSingleton(); } return(_instance); }
static void Main(string[] args) { OldSingleton os1 = OldSingleton.Instance(); OldSingleton os2 = OldSingleton.Instance(); os1.Name = "This is old singleton class!!"; Console.WriteLine(os2.Name); NewSingleton ns1 = NewSingleton.Instance(); NewSingleton ns2 = NewSingleton.Instance(); ns1.Name = "This is new singleton class!!"; Console.WriteLine(ns2.Name); OptimizeSingleton ops1 = OptimizeSingleton.Instance(); OptimizeSingleton ops2 = OptimizeSingleton.Instance(); ops1.Name = "This is new C# optimize singleton class!!"; Console.WriteLine(ops2.Name); Console.ReadKey(); }