project-system VS CsprojToVs2017

The .NET Core one was necessary once. Today msbuild (and I believe VS too) uses heuristics instead, so it does not matter which GUID you use.

The Visual Studio project system is extensible, allowing you to integrate your custom project and SDK right into VS.

From the https://github.com/dotnet/project-system/blob/main/docs/build-acceleration.md

https://github.com/dotnet/project-system/pull/8438 (note: will be available in 17.4)

You can do this via csproj or launch settings by hands, but it won't work, see https://github.com/dotnet/project-system/issues/3690

Did you change the startup form for your project? If so, this is a bug that should be addressed soon. The easiest way out is to undo the change you made to the startup object setting it back to form1.

Sdk at least works with .net standard so shared projects can be converted to that, we also had some success using the MSBuild.SDK.SystemWeb sdk nuget package for our MVC5 projects which I found from the github issue discussions on adding official support for it on older projects.

For sure. If you still have access to the project, file a bug on https://github.com/dotnet/project-system so that someone can fix it for others too.

So this would be related to the project system module in Visual Studio but I am not sure how C++ specifically is handled. Might be worth bringing up here to find out where to report things like this or at least find out why they work the way they do.

Yes, probably. Try the guide at https://learn.microsoft.com/en-us/dotnet/desktop/winforms/migration/?view=netdesktop-7.0. I personally prefer the tool https://github.com/hvanbakel/CsprojToVs2017/, but it's a bit more manual.

There are a few tools that can help in the process. Years back I used a tool named Project2015to2017: https://github.com/hvanbakel/CsprojToVs2017. Since then, Microsoft also released a tool: https://github.com/dotnet/upgrade-assistant. There was also this tool but it looks like it has been discontinued: https://github.com/microsoft/dotnet-apiport

https://github.com/hvanbakel/CsprojToVs2017 to convert projects to the new format. This is much nicer in multiple ways: VS doesn’t need to reload the project when it changes, version control changes are much less noisy, you get a Dependencies node in Solution Explorer instead of the old References one, etc.

There is a much better tool for that: https://github.com/hvanbakel/CsprojToVs2017

I've been a bit luckier in that regard, but I'm not sure if your path wouldn't have taken less effort. I use https://github.com/hvanbakel/CsprojToVs2017 (dotnet migrate-2019 wizard) to modernize the projects, then further tweak them by hand. For ASP.NET projects, it's indeed a very difficult road. WebForms outright doesn't exist, and Core is very different from MVC in some areas. https://github.com/CZEMacLeod/MSBuild.SDK.SystemWeb helps somewhat.

there's https://github.com/dotnet/try-convert. Haven't tried it; I instead use https://github.com/hvanbakel/CsprojToVs2017, but I assume the former might be a better choice by now.

I personally used https://github.com/hvanbakel/CsprojToVs2017 to port an existing 450+ projects solution using the old .csproj format to the new one. I had to manually fixup some projects afterwards but overall a good experience.