using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace MSSQL_MVVM_Sample.Structure { public class Singleton where T : class, new() { private static readonly Lazy _instnace = new Lazy(() => new T()); public delegate void ExceptionEventHandler(string id, Exception ex); public static T Instance { get { return _instnace.Value; } } } }