How do I enable the console in a WPF .NET Core application?

Question

I'm trying out WPF .NET Core for the first time, and one of the things I always do in a new WPF .NET Framework project is turn on the console, but I receive an error when I try to do this in .NET Core.

In traditional WPF, targeting .NET Framework, this was fairly simple;

• Set the Build Action for App.xaml to Page
• Define a Main method somewhere, and tag it with the STAThreadAttribute
• In the project settings, set the output type to Console Application, and set the Startup object to wherever you put the Main method

I replicated these steps in the WPF .NET Core, but I get an error when I try to change the Build Action for App.xaml

The error (it occurs immediately after selecting Page in the dropdown in the Properties window):

An error has occurred while saving the edited properties listed below:
    Build Action
One or more values are invalid. 
Cannot add 'App.xaml' to the project, because the path is explicitly excluded from the project 
(C:\Program Files\dotnet\sdk\3.0.100\Sdks\Microsoft.NET.Sdk.WindowsDesktop\targets\Microsoft.NET.Sdk.WindowsDesktop.targets (45,5)).

Does anyone know a way around this, or another way to enable the console in WPF .NET Core?

Answer 1

Setting the following properties will make your WPF application a "Console Application"

<PropertyGroup>
  <OutputType>Exe</OutputType>
  <DisableWinExeOutputInference>true</DisableWinExeOutputInference>
</PropertyGroup>

The SDK automatically change OutputType from Exe to WinExe for WPF and WinForms apps. See https://learn.microsoft.com/en-us/dotnet/core/compatibility/windows-forms/5.0/automatically-infer-winexe-output-type

Answer 2

After some trial and error, I figured out that the .csproj file got messed up. I don't know how exactly it went wrong, I suspect it had to do with editing the project through its Properties window in that version of VS2019.

I edited the .csproj by hand, and it works if it looks as follows:

<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <UseWPF>true</UseWPF>
    <ApplicationIcon />
    <StartupObject>ProjectName.App</StartupObject>
  </PropertyGroup>

  <ItemGroup>
    <Page Include="App.xaml"></Page>
  </ItemGroup>

  <ItemGroup>
    <ApplicationDefinition Remove="App.xaml"></ApplicationDefinition>      <--- key part
  </ItemGroup>

</Project>

I checked the .csproj file for a working .NET Framework project, and the key seems to be removing App.xaml as ApplicationDefinition by hand, as the .NET Framework .csproj did not have that section in it.