init

Common/DTS.CommonCore/Classes/Singleton.cs

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+using System;
+
+namespace DTS.Common.Classes
+{
+    /// <summary>
+    /// This is the generic for singletons.
+    /// </summary>
+    /// <typeparam name="T">Type of derived Singleton object (i.e. class MySingletone: Singleton&lt;MySingleton&gt;).</typeparam>
+    public class Singleton<T> where T : new()
+    {
+        /// <summary>
+        /// This is a protected constructor.
+        /// </summary>
+        protected Singleton()
+        {
+            if (!ReferenceEquals(Instance, null))
+                throw new InvalidOperationException("You have tried to create a new singleton class where you should have instanced it. Replace your \"new class()\" with \"class.Instance\"");
+        }
+
+        /// <summary>
+        /// Gets the singleton instance of type T.
+        /// </summary>
+        public static T Instance
+        {
+            get
+            {
+                if (SingletonCreator.exception != null)
+                    throw SingletonCreator.exception;
+
+                return SingletonCreator.instance;
+            }
+        }
+
+        /// <summary>
+        /// Creates the singleton instance of type T.
+        /// </summary>
+        // ReSharper disable once ClassNeverInstantiated.Local
+        private class SingletonCreator
+        {
+            internal static readonly T instance;
+            internal static readonly Exception exception;
+
+            /// <summary>
+            /// Creates the singleton instance of type T.
+            /// </summary>
+            static SingletonCreator()
+            {
+                try
+                {
+                    instance = new T();
+                }
+                catch (Exception ex)
+                {
+                    exception = ex.InnerException ?? ex;
+                    Console.WriteLine(@"Singleton: {0}", exception);
+                }
+            }
+        }
+    }
+}