using System;

using System.Linq;

using System.Collections;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var keyList = new int[]{1,2,3,4,5};

        IDictionary<int,string> resultDict = new FakeFastDictionary<int,string>();

        foreach (var key in keyList)

        {

            resultDict.Add(key, "someResult");

        }

        foreach (var key in resultDict.Keys)

        {

            Console.WriteLine((key));

        }

        foreach (var value in resultDict.Values)

        {

            Console.WriteLine((value));

        }

    }

}

​

    public class FakeFastDictionary<TKey, TValue> : Dictionary<TKey, TValue>

    {

        protected IList<KeyValuePair<TKey, TValue>> _list

            = new List<KeyValuePair<TKey, TValue>>();

​

        public new void Add(TKey key, TValue value)

        {

            _list.Add(new KeyValuePair<TKey, TValue>(key, value));

        }

​

        public new ICollection<TValue> Values

        {

​

            get

            {

                // there may be faster ways to to it:

                return _list.Select(x => x.Value).ToArray();

            }

        }

​

        public new ICollection<TKey> Keys

        {

            get

            {

                // there may be faster ways to to it:

                return _list.Select(x => x.Key).ToArray();

            }

        }

    }

​

​