private void chart_Click(object sender, EventArgs e)  {  
     try   {    
        NPostbackEventArgs eventArgs = e as NPostbackEventArgs;    
        NDataPoint dp = eventArgs.Id.FindInDocument(chart.Document) as NDataPoint;    
        if (dp != null)    {     
        ...
        }  
    }   catch (Exception)  
    {  
    } 
}

        chart.BackgroundStyle.FrameStyle.Visible = false;
        chart.Panels.Clear();
        chart.Charts.Clear();
        chart.Legends.Clear();
       
        NLegend legend = new NLegend();
        legend.DockMode = PanelDockMode.Bottom;
        legend.Data.ExpandMode = LegendExpandMode.ColsFixed;
        legend.Data.ColCount = 2;
        legend.Mode = LegendMode.Automatic;
        legend.BoundsMode = BoundsMode.Fit;
        legend.OuterLeftBorderStyle.Width = new NLength(0);
        legend.OuterTopBorderStyle.Width = new NLength(0);
        legend.OuterRightBorderStyle.Width = new NLength(0);
        legend.OuterBottomBorderStyle.Width = new NLength(0);
        legend.HorizontalBorderStyle.Width = new NLength(0);
        legend.VerticalBorderStyle.Width = new NLength(0);
        legend.FillStyle.SetTransparencyPercent(100);
        legend.Visible = true;
        chart.Panels.Add(legend);

        NCartesianChart chart = new NCartesianChart();
        chart.DockMode = PanelDockMode.Fill;
        chart.BoundsMode = BoundsMode.Stretch;
        chart.DisplayOnLegend = legend;
        chart.Margins = new NMarginsL(0, 10, 0, 0);
        chart.Visible = true;
        chart.Panels.Add(chart);

        NScaleStripStyle stripStyle = new NScaleStripStyle();
        stripStyle.SetShowAtWall(ChartWallType.Back, true);
        stripStyle.Interlaced = true;
        stripStyle.Begin = 0;
        stripStyle.End = 10;
        stripStyle.Infinite = true;
        stripStyle.Interval = 1;
        stripStyle.Length = 1;

        NScaleConfigurator YScale = chart.Axis(StandardAxis.PrimaryY).ScaleConfigurator;
        YScale.StripStyles.Clear();
        YScale.StripStyles.Add(stripStyle);
        YScale.Title.Text = Resources.Resource.titleValuationIndex;

        NAxis secYAxis = chart.Axis(StandardAxis.SecondaryY);
        secYAxis.Visible = true;
        secYAxis.Anchor = new NDockAxisAnchor(AxisDockZone.FrontRight, true);
        NLinearScaleConfigurator SYScale = secYAxis.ScaleConfigurator as NLinearScaleConfigurator;
        SYScale.MajorGridStyle.ShowAtWalls = new ChartWallType[] { };
        SYScale.Title.Text = "Relative Movement";

        NDateTimeScaleConfigurator dateTimeScale = new NDateTimeScaleConfigurator();
        dateTimeScale.LabelStyle.Angle = new NScaleLabelAngle(ScaleLabelAngleMode.Scale, 90);
        dateTimeScale.LabelStyle.ContentAlignment = ContentAlignment.TopLeft;
        chart.Axis(StandardAxis.PrimaryX).ScaleConfigurator = dateTimeScale;
        setValIndexXAxisInterval();

        NLineSeries lineValIndex = (NLineSeries)chart.Series.Add(SeriesType.Line);
        lineValIndex.Name = Resources.Resource.titleValuationIndex;
        lineValIndex.InflateMargins = true;
        lineValIndex.DataLabelStyle.Visible = false;
        lineValIndex.MarkerStyle.Visible = true;
        lineValIndex.MarkerStyle.PointShape = PointShape.Cylinder;
        lineValIndex.ShadowStyle.Type = ShadowType.GaussianBlur;
        lineValIndex.ShadowStyle.Offset = new NPointL(3, 3);
        lineValIndex.ShadowStyle.FadeLength = new NLength(5);
        lineValIndex.UseXValues = true;

        NLineSeries lineValIndexIndex = (NLineSeries)chart.Series.Add(SeriesType.Line);
        lineValIndexIndex.Name = Resources.Resource.titleIndex;
        lineValIndexIndex.Visible = false;
        lineValIndexIndex.InflateMargins = true;
        lineValIndexIndex.UseXValues = true;
        lineValIndexIndex.DataLabelStyle.Visible = false;
        lineValIndexIndex.MarkerStyle.Visible = false;
        lineValIndexIndex.DisplayOnAxis(StandardAxis.PrimaryY, false);
        lineValIndexIndex.DisplayOnAxis(StandardAxis.SecondaryY, true);

         ... Fill chart series and set NMarkerStyles as needed

        NHtmlImageMapResponse imageMapResponse = new NHtmlImageMapResponse();
        imageMapResponse.GridCellSize = 2;
        chart.ServerSettings.BrowserResponseSettings.DefaultResponse = imageMapResponse;

        chart.Click += new EventHandler(chart_Click);