Creating a chart in C# WinForms .NET 6

WinForms has been depreciated and a lot of its functionality hasn't made it into .NET 6. There are no plans to change this. If you find an alternative solution please share it.

See this for more info: https://github.com/dotnet/winforms/discussions/6163

So, I found a work-around. It's not the most elegant, nor particularly performant, but since I just wanted a quick visualisation tool for internal testing, this did the trick nicely. Here's what I ended up with (basic scatter plot, but the principle can be adapted for line charts and box charts etc):

Process

1. Add a picture box to your form
2. populate it with an empty bitmap to the scale that you want to display
3. for each data point you want to plot, draw a circle on the bitmap at those coordinates using Graphics.DrawEllipse

Example Code

    private void PlotCoordinates(List<Coordinates> coordinateList, Pen pen)
    {
        List<Rectangle> boundingBoxes = GenerateBoundingBoxes(coordinateList);

        using (Graphics g = Graphics.FromImage(image))
        {
            foreach (Rectangle boundingBox in boundingBoxes)
            {
                g.DrawEllipse(pen, boundingBox);
            }
        }
    }

    private List<Rectangle> GenerateBoundingBoxes(List<Coordinates> coordinateList)
    {
        var boundingBoxes = new List<Rectangle>(coordinateList.Count);

        //dataPointDiameterPixels is the diameter you want your ellipse to be on the plot
        //it needs to be an odd to be accurate
        int dataPointCetralisingOffset = dataPointDiameterPixels / 2;
        int rectLength = dataPointDiameterPixels;

        foreach (Coordinates coordinates in coordinateList)
        {
            int topLeftX = Maths.Max(coordinates.X - dataPointCetralisingOffset, 0);
            int topLeftY = Maths.Max(coordinates.Y - dataPointCetralisingOffset, 0);

            var box = new Rectangle(topLeftX, topLeftY, rectLength, rectLength);
            boundingBoxes.Add(box);
        }

        return boundingBoxes;
    }

Kirsan created a fork that works with .NET 6

https://github.com/kirsan31/winforms-datavisualization