You can easily perform a hit test using the following code:
void nChartControl1_MouseMove(object sender, MouseEventArgs e)
NHitTestResult result = nChartControl1.HitTest(e.X, e.Y);
if (result.Series as NLineSeries != null)
// result.Series holds a reference to the clicked line;
The All Examples\Interactivity\Mouse Events group of examples show how to perform hit testing in general. Just let us know if you have any questions...
Nevron Support Team