.net visual-studio msbuild csproj target-framework

How to change targetframework based on Visual Studio version

I would like to support from .NET Standard 2.0 to .NET 8.0 every target in a projects. Currently

<TargetFrameworks>$(ExtraTargetFrameworks)netstandard2.0</TargetFrameworks>

is used along with

<Project>
    <PropertyGroup>
        <ExtraTargetFrameworks></ExtraTargetFrameworks>
    </PropertyGroup>
    <PropertyGroup Condition="'$(UseDotnet6SDK)'=='True'">
        <ExtraTargetFrameworks>net6.0;</ExtraTargetFrameworks>
    </PropertyGroup>
</Project>

I would just add net8.0 to the TargetFrameworks, but that's a bit problematic for the following reasons:

Windows 7 and 8.1 are no longer supported platforms as of .NET 7
Visual Studio 2022 no longer supports Windows 7 and 8.1
.NET 7 and later not supported by into Visual Studio 2019 or older
Visual Studio refuses to deal with a project unless it can handle all of the project's TargetFrameworks, meaning
```
  <TargetFrameworks>net5.0;net8.0</TargetFrameworks>` 
```
won't suffice

So the question is: how to include net8.0 in TargetFrameworks if using Visual Studio 2022 or later or not using Visual Studio at all, but not when using an older version of Visual Studio?

I was thinking of adding conditions to the property groups, like so:

<PropertyGroup Condition="'$(Flavor)'=='DEBUG'">

based on this

I have found a list of reserved properties, that I assume could be used in conditions here, but this does not list a way of querying the Visual Studio version - although some paths listed usually contain the version. Would it be possible to regex magic that for the condition?

I don't want to specify properties on the command line, all should be in the .csproj or in other build/project files.

Solution

If you want to change targetframework based on visual studio version, you can use property VisualStudioVersion. For more information, please check the Common MSBuild project properties

For example

<Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
<Target Name="PrintVisualStudioInfo">
    <Message Text="VisualStudioVersion: '$(VisualStudioVersion)'" />
</Target>

<Project>
    <PropertyGroup>
        <ExtraTargetFrameworks></ExtraTargetFrameworks>
    </PropertyGroup>
    <PropertyGroup Condition="'$(VisualStudioVersion)'=='17.0'">
        <ExtraTargetFrameworks>net8.0;</ExtraTargetFrameworks>
    </PropertyGroup>
</Project>

Hope it can help you.