Workaround to use the designer in WPF Core App (.netCore WPF).

CoreHiWPF: An executable WPF Core application project, need to open with Visual Studio 2019.

Reference:

dotnet/samples - WPF Hello World sample with linked files

Firstly, you need to Install vs 2019 Professional/Enterprise version. Then installing .net core 3.0 SDK is needed. Now you can try to create a .net core WPF application,

After setting the relevant project name and storage path, it will pop up:

After setting done, restart vs to take effect.

Now the file structure of the solution is below:

Right click the project CoreHiWPF, select Properties, then change its Assembly Name to HiWPF.

Then right click the project, click "Edit CoreHiWPF.csproj".

Add code as below:

  <ItemGroup>
    <ApplicationDefinition Include="..\HiWPF\App.xaml" Link="App.xaml">
      <Generator>MSBuild:Compile</Generator>
    </ApplicationDefinition>
    <Compile Include="..\HiWPF\App.xaml.cs" Link="App.xaml.cs" />
  </ItemGroup>

  <ItemGroup>
    <Page Include="..\HiWPF\MainWindow.xaml" Link="MainWindow.xaml">
      <Generator>MSBuild:Compile</Generator>
    </Page>
    <Compile Include="..\HiWPF\MainWindow.xaml.cs" Link="MainWindow.xaml.cs" />
  </ItemGroup>

If the .net core WPF project CoreHiWPF is already highlighted, you can ignore then. Or, you need to select project CoreHiWPF, then right click Set As Start up project.

Now close all opened files. Click the file MainWindow.xaml of project HiWPF. Then you can see empty WPF window in XAML designer now.

Then, I add two lines to Grid of the file MainWindow.xaml:

• One line is a Label which support Wrap
• The other line is a Exit button.

Then I added the Click event to Exit button, added the Loaded event to Window.

After finish updating code, press F5 to run, the final UI is below:

The code is pushed to github:

.netCore-WPF_Designer .

Reference：

dotnet/samples - WPF Hello World sample with linked files

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