Hi Simon,
You'll need to create a second point series that has per point tooltips and disable the markers of the line if you want to achieve this effect:
NChart chart = nChartControl1.Charts[0];
NLineSeries line = new NLineSeries();
line.DataLabelStyle.Visible = false;
line.MarkerStyle.Visible = false;
for (int i = 0; i < 3; i++)
{
line.Values.Add(i);
}
NPointSeries point = new NPointSeries();
for (int i = 0; i < line.Values.Count; i++)
{
point.Values.Add(line.Values[i]);
point.InteractivityStyles.Add(i, i.ToString());
}
chart.Series.Add(point);
chart.Series.Add(line);
nChartControl1.Controller.Tools.Add(new NTooltipTool());
Hope this helps - let us know if you meet any problems.