Uneven (custom) intervals on chart

Question

This is what I currently have:

What I need, is to have the following uneven intervals (vertical lines & x-axis labels):

1) 1 (i.e. must not cross at 0)
2) 1.5
3) 2.5
4) 3.5
5) 4

Is there any way to do this? Even if it's a kludge with an extra series or something - although I'm hoping it's something to do with IntervalOffset, but I can't get it to do what I want.

Currently, I just have:

chartarea.AxisX.Maximum = 4;
chartarea.AxisX.Minimum = 1;
chartarea.AxisX.Interval = 1;

Answer 1

This is what was required:

// set the max & min, with an interval of 1 which is offset by 0.5
// this gives the correct start (1), and three .5 intervals
// however, it doesn't give the closing vertical line at 4
chartarea.AxisX.Maximum = 4;
chartarea.AxisX.Minimum = 1;
chartarea.AxisX.Interval = 1;
chartarea.AxisX.IntervalOffset = 0.5;

// enable a secondary y axis for the line at 4
chartarea.AxisY2.Enabled = AxisEnabled.True;
// switch of all tickmarks & gridlines
chartarea.AxisY2.MajorTickMark.Enabled = false;
chartarea.AxisY2.MinorTickMark.Enabled = false;
chartarea.AxisY2.MajorGrid.Enabled = false;
chartarea.AxisY2.MinorGrid.Enabled = false;
chartarea.AxisY2.LabelStyle.Enabled = false;
// set the correct colour  & line style
chartarea.AxisY2.LineColor = Color.FromArgb(160, 160, 160);
chartarea.AxisY2.LineDashStyle = ChartDashStyle.Dash;

// add custom labels for the 5 points/lines
chartarea.AxisX.CustomLabels.Add(0.9, 1.1, "1");
chartarea.AxisX.CustomLabels.Add(1.4, 1.6, "1.5");
chartarea.AxisX.CustomLabels.Add(2.4, 2.6, "2.5");
chartarea.AxisX.CustomLabels.Add(3.4, 3.6, "3.5");
chartarea.AxisX.CustomLabels.Add(3.9, 4.1, "4");

And voila: (although my data has changed)