I am able to get the viewRange on ZoomIn and ZoomOut through the DataZoom Tool's EndDrag Event as:

void chartDataZoomTool_EndDrag(object sender, EventArgs e)
        {
            chartControl.Document.Calculate();
            chartControl.Document.RecalcLayout(chartControl.View.Context);

            NRange1DD xAxisRange = chart.Axis(StandardAxis.PrimaryX).Scale.RulerRange;
            DateTime startdate = DateTime.FromOADate(xAxisRange.Begin);
            DateTime enddate = DateTime.FromOADate(xAxisRange.End);

            System.Diagnostics.Debug.WriteLine("Zoom Tool EndDrag: StartDate" + startdate + "- End Date:" + enddate);          
        }

I have subscribed to the PrimaryXAxis's Scrollbar events and other events giving correct values except the ZoomOut event.

Axis Initialization:

private void InitializePrimaryXAxis()
{
    chartPrimaryXAxis = chart.Axis(StandardAxis.PrimaryX);
    // X Axis Configuration

    dateTimeScale = new NDateTimeScaleConfigurator();
    dateTimeScale.Title.Text = string.Empty;
    dateTimeScale.LabelStyle.Angle = new NScaleLabelAngle(ScaleLabelAngleMode.Scale, 90);
    dateTimeScale.LabelStyle.ContentAlignment = ContentAlignment.MiddleCenter;
    dateTimeScale.LabelStyle.TextStyle.FontStyle = new NFontStyle("Times New Roman", 10);
    dateTimeScale.LabelFitModes = new LabelFitMode[] { LabelFitMode.AutoScale };
    chartPrimaryXAxis.ScaleConfigurator = dateTimeScale;
    chartPrimaryXAxis.ScrollBar.Visible = true;
    chartPrimaryXAxis.ScrollBar.ResetButton.Visible = true;
    chartPrimaryXAxis.ScrollBar.ShowSliders = true;
    chartPrimaryXAxis.ScrollBar.Reset += new EventHandler(ScrollBar_Reset);
    chartPrimaryXAxis.ScrollBar.BeginValueChanged += new EventHandler(ScrollBar_BeginValueChanged);
    chartPrimaryXAxis.ScrollBar.EndValueChanged += new EventHandler(ScrollBar_EndValueChanged);
    chartPrimaryXAxis.ScrollBar.ViewRangeChanged += new EventHandler(ScrollBar_ViewRangeChanged);
    dateTimeScale.EnableUnitSensitiveFormatting = true;
    dateTimeScale.RoundToTickMax = false;
    dateTimeScale.RoundToTickMin = false;
}

// Reset Event

void ScrollBar_Reset(object sender, EventArgs e)
{               
    NRange1DD xAxisRange = new NRange1DD(chartPrimaryXAxis.ScrollBar.BeginValue, chartPrimaryXAxis.ScrollBar.EndValue);
    //NRange1DD xAxisRange = chart.Axis(StandardAxis.PrimaryX).Scale.RulerRange;
    DateTime startdate = DateTime.FromOADate(xAxisRange.Begin);
    DateTime enddate = DateTime.FromOADate(xAxisRange.End);
    NScrollBar scrollbar = (sender as NScrollBar);
    System.Diagnostics.Debug.WriteLine("ScrollBar EndValueChanged: StartDate" + 
        DateTime.FromOADate(scrollbar.BeginValue) + "- End Date:" + DateTime.FromOADate(scrollbar.EndValue));

    System.Diagnostics.Debug.WriteLine("Horizontal Axis Begin Value" + startdate.ToString());
    System.Diagnostics.Debug.WriteLine("Horizontal Axis End Value" + enddate.ToString());
}

When i get value on Reset event it return the view range before the page view zoom out.

Question 1: How can i get updated Zoom PagingView Range on Reset event.
Question 2: How can i full Axis Range with paging?? example i have XValues 1 Jan to 31 Dec then which Axis property will let me know this at run time??
Question 3: What is the best way to get the Current Chart View Page begin and end values ( Range)?