Winforms chart: how to enable background color gau

问题:

I'm looking for a way to enable custom background color gauge in the Winform chart control library. Here is an example:

See the green, yellow, and red color in the background?

Now, I need is a way to customize the background color gauge by controlling the starting/ending Y values, the color itself, as well as the number of different colors.

Thanks in advance!

回答1:

You can do that by adding StripLines to the y-Axis of the ChartArea.

Their positions and sizes are controlled by their StripWidth, Interval and IntervalOffset properties.

All values are set in data values, so in the example above the three lines, bottom to top have StripWidth of 30, 40 and 30; their IntervalOffsets are 0, 30 and 70 and all have an Interval of 0, which means they don't repeat.

Let's try it:

Axis ay = chart1.ChartAreas[0].AxisY;
ay.Minimum = 0;
ay.Maximum = 100;

StripLine sl0 = new StripLine();
sl0.BackColor = Color.FromArgb(64, Color.LightSeaGreen);
sl0.StripWidth = 30;
sl0.IntervalOffset = 0;

StripLine sl1 = new StripLine();
sl1.BackColor = Color.FromArgb(64, Color.LightGoldenrodYellow);
sl1.StripWidth = 40;
sl1.IntervalOffset = 30;

StripLine sl2 = new StripLine();
sl2.BackColor = Color.FromArgb(64, Color.LightSalmon);
sl2.StripWidth = 30;
sl2.IntervalOffset = 70;

chart1.ChartAreas[0].AxisY.StripLines.Add(sl0);
chart1.ChartAreas[0].AxisY.StripLines.Add(sl1);
chart1.ChartAreas[0].AxisY.StripLines.Add(sl2);