Yesterday I demonstrated how we could use the .NET Upgrade Assistant to help us port a 10 year old WinForms application to .NET Core. We tried the 'analyze' mode to do a dry-run of the upgrade process.
Today I continue with a follow-up post where we have a look at the warnings and diagnostic messages I got and see how we can get rid of them.
Warning - HighDpiMode
We’ll start easy with the following warning:
HighDpiMode needs to set in Main() instead of app.config or app.manifest - Application.SetHighDpiMode(HighDpiMode.<setting>). It is recommended to use SystemAware as the HighDpiMode option for better results.
As I’m not using the HighDpiMode in my application, I can just ignore this warning (see this related Github issue: https://github.com/dotnet/upgrade-assistant/issues/980). If you need to set the HighDpiMode, have a look at the changed bootstrapping logic here: https://docs.microsoft.com/en-us/dotnet/core/compatibility/windows-forms/6.0/application-bootstrap.
Warning – Detected package downgrade
Let’s move on to the next warning:
[WRN] [NuGet] Detected package downgrade: System.ServiceModel.Security from 4.9.0 to 4.8.1. Reference the package directly from the project to select a different version. project -> Microsoft.Windows.Compatibility 6.0.0 -> System.ServiceModel.Security (>= 4.9.0) project -> System.ServiceModel.Security (>= 4.8.1)
These warnings are caused by the Microsoft.Windows.Compability NuGet package. This package will introduce a reference to a lot of other packages(with some System.ServiceModel related dependencies as a part of them).
The original application was using the 4.8.1 versions of those packages. Upgrading to 4.9.0 should not be a problem. This means that this warning will disappear once all projects in the solution are upgraded.
Another one that we can safely ignore. Nice!
Another log line that triggered my attention was the following:
Diagnostic UA0002 with the message This type is not supported on .NET Core/.NET 5+ and should be replaced with a modern equivalent’
I had a look at the Analysis.sarif file that was generated as part of the analyze process. Unfortunately that didn’t gave any extra clue on what this message was referring to.
There is an open Github issue related to this: https://github.com/dotnet/upgrade-assistant/issues/1102
So we had to skip this message as I didn’t know what to do.
The last log message I want to have a look at is the following one:
Diagnostic UA0013_I with the message Windows Forms Deprecated controls : Microsoft.Reporting.WinForms.ReportViewer is no longer supported’
Microsoft provided a solution in the form of an updated ReportViewer WinForms control that can be downloaded from the Visual Studio Marketplace here: https://marketplace.visualstudio.com/items?itemName=ProBITools.MicrosoftRdlcReportDesignerforVisualStudio2022