I did use that link to create a custom grid line using the following code.
CustomGridline gridline = new CustomGridLine();
gridline.XIntercept = collection.Date.ToOADate();
gridline.StrokeThickness = .3;
Then I move the grid line using the following code. I am not sure how to convert the position X to a date value. I cannot use TOaDate() as it gives some wrong date. if I use position.x -67 then I get somewhat close coordinates for the cursor but not exact. How do you solve this.
void ChartArea_MouseMove(object sender, MouseEventArgs e)
ChartArea plotAreaPanel = sender as ChartArea;
var position = e.GetPosition(plotAreaPanel);
double posX = double.Parse(position.X.ToString());
var x = plotAreaPanel.AxisX.ConvertPhysicalUnitsToData(posX -67);
AnnotationCollection cGridCollection1 = chart.DefaultView.ChartArea.Annotations;
if (cGridCollection1.Count == 1)
as CustomGridLine).XIntercept = x;