using System;

using System.Collections.Concurrent;

using System.Threading;

​

namespace ConsoleApp19

    {

    public class Program

        {

        [Flags]

        public enum OidcScopes

            {

            PwProjectsRead = 1,

            PwConnectionsRead = 2,

            PwdiRead = 4,

            PwdiWrite = 8

            }

​

        static ConcurrentDictionary<OidcScopes, object> _dictionary = new ConcurrentDictionary<OidcScopes, object> ();

​

        public static void Main (string[] args)

            {

            for (int i = 0; i < 8; i++)

                {

                new Thread (() =>

                     {

                     var x = GetOrAdd (OidcScopes.PwdiRead);

                     })

                    .Start ();

                }

​

            Thread.Sleep (1000);

            }

​

        static object GetOrAdd (OidcScopes scope)

            {

            //lock (_dictionary)

            {

                return _dictionary.GetOrAdd (scope, scopes => Create(scopes));

            }

            }

​

        private static object Create (OidcScopes scope)

            {

            Console.WriteLine (scope);

            return new object ();

            }

        }

    }

​