read data from chart, ms as x value - charts

Question

i have some trouble with adding pinots to a chart and read them back to an array.
with tis code iam adding a new piont to my chart, y_value is a normal double var
time_stamp is a string with the current daytime (15:56:45:799) with millisecounds
string time_stamp = DateTime.Now.ToLongTimeString() + ":" + DateTime.Now.Millisecond.ToString();
chart_logger.Series[0].Points.AddXY(time_stamp, y_value);
after plotting the chart i want to save alle datapionts in an txt file, so i want the read all points form the chart
i tried it with
DataPoint[] asd = chart_logger.Series[0].Points.ToArray();
it read all the y values from the chart but i the x values are always zero
does someone have any idea
thanks for the help
Ralf

Answer 1

You need to use `ToOADate()' and 'FromOADate(double d)'.
chart_logger.Series[0].XValueType = ChartValueType.DateTime;
chart_logger.ChartAreas[0].AxisX.LabelStyle.Format = "MM/dd/yyyy HH:mm:ss.fff";
chart_logger.Series[0].Points.AddXY(DateTime.Now.ToOADate(), y_value);
DataPoint[] asd = chart_logger.Series[0].Points.ToArray();
var x = DateTime.FromOADate(asd[0].XValue);
Or
chart_logger.Series[0].YValuesPerPoint = 2;
var time = DateTime.Now;
string time_stamp = time.ToLongTimeString() + ":" + time.Now.Millisecond.ToString();
chart_logger.Series[0].Points.AddXY(time_stamp, y_value, time.ToOADate());
DataPoint[] asd = chart_logger.Series[0].Points.ToArray();
var x = DateTime.FromOADate(asd[0].YValues[1]);