mschart control how do you add crosshairs and know the value of x and y on the line?

I have a chart control which shows a curved line.  I want to add crosshairs so when a user mouses over, I can locate the position that x and y coordinates and figure out the value of the line at that point.

I can add them using this:

I am not sure how to capture the values as it relates to my line though.

Here is the code to create my line:
List<double> theoreticalPrices = new List<double>();
for (double i = 0; i < 100; i = i + .1)
      foreach (OrderChain.OpenContracts openContractse in TsalChain.GetOpenContracts())
            totalAtThisStrike += openContractse.price;
      chart1.Series["Series1"].Points.Add(new DataPoint(i, totalAtThisStrike));
chart1.Series["Series1"].ChartType = SeriesChartType.Line;
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Robert SchuttSoftware EngineerCommented:
I added a label to the form for testing and added the below code to the MouseMove function. I think it does what you need:
            string yval = "N/A";
            int pointMax = chart1.Series["Series1"].Points.Count - 1;
            int pointNum = -1;
            try {
                double xval = Math.Min(chart1.ChartAreas["ChartArea1"].AxisX.Maximum, Math.Max(chart1.ChartAreas["ChartArea1"].AxisX.Minimum, chart1.ChartAreas["ChartArea1"].AxisX.PixelPositionToValue(_point.X)));
                pointNum = (int)Math.Round(pointMax * (xval - chart1.ChartAreas["ChartArea1"].AxisX.Minimum) / (chart1.ChartAreas["ChartArea1"].AxisX.Maximum - chart1.ChartAreas["ChartArea1"].AxisX.Minimum));
                yval = chart1.Series["Series1"].Points[pointNum].YValues[0].ToString();
            catch (Exception) {
            label1.Text = string.Format("point {0} of {1}, y value = {2}", 1 + pointNum, chart1.Series["Series1"].Points.Count, yval);

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