Win7, VSCode, F# Interactive. Could not load file or assembly 'System.Windows.Forms.DataVisualization"

[BogusAltay]

Hello, All!

As far as I understand, System.Windows.Forms.DataVisualization is a system assembly. You don't need to explicitly refer to it. Why FSharp.Charting can't find an assembly? See attachment. What am I doing wrong?

[Hydraxize]

Do we have an update on this error? FSharp.Charting is unusable in interactive at the moment. I've tried to load the missing dll with this input at the start of the program: #I @"C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\" The interactive console will show the binding: Binding session to 'C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.8\System.Windows.Forms.DataVisualization.dll'... But the error remains the same. Reference to any other assembly versions didn't solve the issue. Can we have a link to the System.Windows.Forms.DataVisualization.dll we need to refer to?

[dsyme]

You're running F# Interactive for .net core. You will need to use .net framework. I believe only Visual Studio has a legacy switch for running fsi for .net framework from the IDE.

You can run it from the command line using "fsi" from a vs2022 developer prompt.

I don't know if System.Windows.Forms.DataVisualization.dll is available for netcoreapp/net5/6, if it is we could add support for that

[dsyme]

Looks like it's all considered deprecated for netcore, unless someone else is maintaining a fork.

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

Still there is a partial nuget available. Perhaps it's enough to use in practice

[Hydraxize]

Thanks @dsyme, the fsi command in vs2022 developer prompt is doing the job. I'll let the Interactive programming aside for now.

[nightroman]

FWIW, I am able to use the copy of FSharp.Charting.fs with https://github.com/dotnet/winforms-datavisualization in net6.0 scripting with FSharp.Compiler.Service. I had to comment out the context menu code (to be continued). But overall it all works well.

[nightroman]

The menu issue is solved - in net core apps ContextMenuStrip is used instead of ContextMenu.

              let menu = new ContextMenuStrip()
              let dlg = new SaveFileDialog(Filter = "PNG (*.png)|*.png|Bitmap (*.bmp;*.dib)|*.bmp;*.dib|GIF (*.gif)|*.gif|TIFF (*.tiff;*.tif)|*.tiff;*.tif|EMF (*.emf)|*.emf|JPEG (*.jpeg;*.jpg;*.jpe)|*.jpeg;*.jpg;*.jpe|EMF+ (*.emf)|*.emf|EMF+Dual (*.emf)|*.emf")
              let miCopy = new ToolStripMenuItem("&Copy Image to Clipboard", ShortcutKeys = (Keys.Control ||| Keys.C))
              let miCopyEmf = new ToolStripMenuItem("Copy Image to Clipboard as &EMF", ShortcutKeys = (Keys.Control ||| Keys.Shift ||| Keys.C))
              let miSave = new ToolStripMenuItem("&Save Image As..", ShortcutKeys = (Keys.Control ||| Keys.S))
              let miEdit = new ToolStripMenuItem("Show Property &Grid", ShortcutKeys = (Keys.Control ||| Keys.G))

              miEdit.Click.Add(fun _ -> 
                  miEdit.Checked <- not miEdit.Checked
                  props.Visible <- miEdit.Checked)

              miCopy.Click.Add(fun _ ->        
                  srcChart.CopyChartToClipboard())

              miCopyEmf.Click.Add(fun _ ->
                  srcChart.CopyChartToClipboardEmf(self))

              miSave.Click.Add(fun _ ->
                  if dlg.ShowDialog() = DialogResult.OK then
                      let fmt = 
                          match dlg.FilterIndex with
                          | 1 -> ChartImageFormat.Png
                          | 2 -> ChartImageFormat.Bmp
                          | 3 -> ChartImageFormat.Gif
                          | 4 -> ChartImageFormat.Tiff
                          | 5 -> ChartImageFormat.Emf
                          | 6 -> ChartImageFormat.Jpeg
                          | 7 -> ChartImageFormat.EmfPlus
                          | 8 -> ChartImageFormat.EmfDual
                          | _ -> ChartImageFormat.Png
                      chart.SaveImage(dlg.FileName, fmt  |> int |> enum) )

              menu.Items.Add(miCopy) |> ignore
              menu.Items.Add(miCopyEmf) |> ignore
              menu.Items.Add(miSave) |> ignore
              menu.Items.Add(miEdit) |> ignore
              self.ContextMenuStrip <- menu