/// <summary>
 /// Update the price information.
 /// </summary>
 /// <param name="fields">PriceSubscriptionFields</param>
 private void updatePrices(PriceSubscriptionFields fields)
 {
     txtBidPrice.Text = fields.GetBestBidPriceField().Value.ToString();
     txtAskPrice.Text = fields.GetBestAskPriceField().Value.ToString();
     txtLastPrice.Text = fields.GetLastTradedPriceField().Value.ToString();
     txtChange.Text = fields.GetNetChangeField().Value.ToString();
 }