C#

class Program
    {
//Client mapping for Server, TCP communication
        static IDictionary<int, string>; ClientMappingDictionary = new Dictionary<int, string>();
        static IList<string> ClientList = new List<string>();
        static IDictionary<string, double> AUMDictionary = new Dictionary<string, double>();

// Security manager manages the security activity. Also generates a IDictionary SecurityMasterDictionary <string,Security>
        static SecurityManager Sec = new SecurityManager();
// Orderbook generator will be used to generate orderbook information for securities
        static Orderbook_Generator OGen = new Orderbook_Generator();

//SecGen randomly generates Securities which returns the list of generated securities.
        static List<Security> A = Sec.SecGen();

// RTD STARTS HERE
[Guid("E128D214-56EF-4AA5-B5D6-7B2283CE2F79"), ProgId("TradeRTD.OrderRTD"), ComVisible(true)]
    public class TradeRTD : MSExcel.IRtdServer
    {
        #region Data Members
        private MSExcel.IRTDUpdateEvent m_callback = null;
        private Timer m_timer = null;
        private IDictionary<int, double> m_topics = new Dictionary<int, double>();

// SecDic is the Security Dictionary Created by the Generator above
        public IDictionary<string, Security> SecDic = Sec.SecurityMasterDictionary;

// Going to take in Topic_1 and Topic_2 to a List <string>
        public List<string> Data = new List<string>();

        #endregion

        #region IRtdServer Interface
        #region ServerStart
        public int ServerStart(MSExcel.IRTDUpdateEvent CallbackObject)
        {
            m_callback = CallbackObject;
            m_timer = new Timer(1000);
            m_timer.Elapsed += new ElapsedEventHandler(m_timer_Elapsed);
            m_timer.Start();
            return 1;
        }
        #endregion

        #region ServerTerminate
        public void ServerTerminate()
        {
            if (null != m_timer)
            {
                m_timer.Stop();
                m_timer.Dispose();
                m_timer = null;
            }
        }
        #endregion

        #region ConnectData
        public object ConnectData(int TopicID, ref Array Strings, ref bool GetNewValues)
        {
           //Convert Strings to List<string> and store
            Data = Strings.OfType<string>().ToList();
            GetNewValues = true;

// get the initial values stored in the history lists.
            double price = SecDic[Data[0]].Price_History.Last();
            double volume = SecDic[Data[0]].Volume_History.Last();
            if (Data[1] == "price")
            {
                if (!m_topics.Keys.Contains(TopicID))
                { m_topics.Add(TopicID, price); }
                else { m_topics.Add(TopicID, volume); }
            }
            return GetData(Data);
        }
        #endregion

        #region DisconnectData
        public void DisconnectData(int TopicID)
        {
            if (m_topics.Keys.Contains(TopicID))
            { m_topics.Remove(TopicID); }
        }
        #endregion

        #region HealthCheck

        public int Heartbeat() { return 1; }
        #endregion

//I THINK THE PROBLEM IS HERE

        #region RefreshData
        public Array RefreshData(ref int TopicCount)
        {
              object[,] data = new object[2, m_topics.Count];
                int idx = 0;
                foreach (string A in SecDic.Keys)
                {
                    data[0, idx] = A;
                    data[1, idx] = SecDic[Data[0]].Price_History.Last();
                    ++idx;
                    data[0, idx] = A;
                    data[1, idx] = SecDic[Data[0]].Volume_History.Last();
                }
            TopicCount = m_topics.Count;
            m_timer.Start();
            return data;
        }
        #endregion

        #endregion
        #region Supporting Methods
        void m_timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            if (null != m_callback)
            {
                m_timer.Stop();
                m_callback.UpdateNotify();
            }
        }

//What data actually needs to be obtained for refreshing data

        private double GetData(List<string> junk)
        {

            if(junk[1] == "price")
                return SecDic[junk[0]].Price_History.Last();
            if (junk[1] == "volume")
                return SecDic[junk[0]].Volume_History.Last();
            else { return 0; }
        }
        #endregion

    }

        static void Main(string[] args)
        { .... orderbook generation and Server starting