protected override void OnRender(ChartControl chartControl, ChartScale chartScale)
{
  base.OnRender(chartControl, chartScale);
  // loop through only the rendered bars on the chart
  for(int barIndex = ChartBars.FromIndex; barIndex <= ChartBars.ToIndex; barIndex++)
  {
    // get the close price at the selected bar index value
    double closePrice = Bars.GetClose(barIndex);
    Print("Bar #" + barIndex + " closing price is " + closePrice);
  }
}