Using System.Windows.Forms classes in a .net core

Question

How can we use classes like Screen in a .NET Core 3.0 WPF project? There are documentation pages for .NET Core 3.0 for them, so I assumed it should work.

VS and the compiler tell me that the namespace Forms does not exist in System.Windows, so it feels like the classes are not in the 3.0 sdk.

There is no System.Windows.Forms package on nuget, and the "Add reference" dialog has only a System_Windows_Forms reference to the .net framework available, which sounds horribly wrong:

Am I missing something?

Answer 1

You should add <UseWindowsForms>true</UseWindowsForms> in your csproj.

<PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <UseWpf>true</UseWpf>
    <UseWindowsForms>true</UseWindowsForms>
</PropertyGroup>