CsprojToVs2017 VS MSBuild.SDK.SystemWeb

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.

I have some projects stuck on that, but not a lot. For web stuff, https://github.com/CZEMacLeod/MSBuild.SDK.SystemWeb does most of the heavy lifting, although things like publishing are broken.

I’ve had great luck with this on older ASP.NET projects https://github.com/CZEMacLeod/MSBuild.SDK.SystemWeb

You can use this unofficial project to modernize your .NET Framework project and take advantage of things like PackageReferences.

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.

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.