void updateTimer_Tick(object sender, EventArgs e)
 {
     //Fetching all the stocks at once in XDocument file
     //XDocument doc = Stock_quotes.FetchQuote(this.getAllSymbolsFromTable(data_table) + ConfigurationManager.AppSettings["DefinedStocks"]);
     //This will update the data_table
     this.addValuesToTheTable(data_table, StockItem.FetchAllStocks(""));
 }
        /// <summary>
        /// Adds a stock symbol to the table or throws an ArgumentException
        /// </summary>
        /// <param name="symbol">symbol(s) to the added. Multiple entries are allowed that are separated by " " or ","</param>
        /// <param name="table"></param>
        public void addStockSymbolToTheTable(string symbol, DataTable table)
        {
            //if (symbol != null && symbol.Length > 0)
            //{
            List <StockItem> list = StockItem.FetchAllStocks(symbol);

            foreach (StockItem stock in list)
            {
                table.Rows.Add(stock.Symbol, stock.CompanyName, stock.CurrentPrice, stock.PercentageOfChangeFromLastDay, stock.FiftyTwoWeekHigh, stock.FiftyTwoWeekLow);
            }
            //}
            //else
            //{
            //    throw new ArgumentException("Added symbol is not accepted as a valid input");
            //}
        }