c# - How to reference System.Windows.Forms in .NET Core 3.0 for WPF apps?

Question

I'm migrating my WPF desktop app from .NET Framework to Core 3.0. I was using System.Windows.Forms.FolderBrowserDialog() and I'm now stuck on how to add this reference to the Core project. There is no "System.Windows.Forms" NuGet package available, is there? Is there any alternative way to display the FolderBrowserDialog in Core?

Update

I created the Core project using the default template and then copied and pasted .cs and .xaml files into it. The .csproj file looks like this:

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <UseWPF>true</UseWPF>
  </PropertyGroup>

Answer 1

You need to add to csproj an additional switch:

<UseWindowsForms>true</UseWindowsForms>

Add it below UseWpf. Then try rebuild. After this, you should be able to use Forms namespace.