Incorrect warning about WindowsDesktop SDK

I have a project that has some libraries/exe that use WPF and some that don’t. The ones that do use the WindowsDesktop SDK. The ones that don’t use the default SDK to prevent accidental WPF references.

I have a directory.build.props file that sets UseWPF to true so that I don’t need them in all places.

In Preview 7, I now get this warning:

1>C:\Program Files\dotnet\sdk\3.0.100-preview7-012503\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.Sdk.DefaultItems.targets(340,5): warning NETSDK1107: Microsoft.NET.Sdk.WindowsDesktop is required to build Windows desktop applications. 'UseWpf' and 'UseWindowsForms' are not supported by the current SDK.

That’s coming from Microsoft.NET.Sdk.DefaultItems.targets. The check is being too aggressive.

[vatsan-madhavan]

We have seen two kinds of problem reports:

i. Failing to change Microsoft.NET.Sdk to Microsoft.NET.Sdk.WindowsDesktop, setting UseWpf (or UseWindowsForms) to true, and attempting to build/port a WPF app (which, unsurprisingly, fails to build as expected)

ii. Using Microsoft.NET.Sdk.WindowsDesktop, but failing to set UseWpf or UseWindowsForms to true. Again, fails to build as expected.

We wanted to add suppressible warnings to help with both scenarios. This addresses the first one.

[vatsan-madhavan]

<PropertyGroup> 
 <MSBuildWarningsAsMessages>$(MSBuildWarningsAsMessages);NETSDK1107</MSBuildWarningsAsMessages>
</PropertyGroup>

That should do it, I think.