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Unpackaged C++-applications can't activate C#-runtime components

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
cpp, csharp
Domain
desktop

Research direction

Start with the CustomControls sample and the CppAppUnpackaged startup project, reproducing the failure during Application::Start. Inspect the activation path for WinUIComponentCs.WinUIComponentCs_XamlTypeInfo.XamlMetaDataProvider, including base.h and factory_cache_entry, and compare the behavior with the working x86 build. Done means the unpackaged C++ sample can activate the C# runtime component without the reported exception.

Written by the indexing model from the issue text.

Description

Steps to reproduce:

  • Clone the repository
  • Open the "CustomControls" sample solution
  • Select CppAppUnpackaged as startup project
  • Run
  • The app halts with an unhandled exception during Application::Start

The error message in the UnhandledException-handler is "Cannot create instance of type 'Microsoft.UI.Xaml.Controls.XamlControlsResources' [Line: 17 Position: 37]"

Setting a breakpoint in base.h, factory_cache_entry, I think that this is related to the activation of "WinUIComponentCs.WinUIComponentCs_XamlTypeInfo.XamlMetaDataProvider".

Apparently, it's not possible currently to activate C#-components in an unpackaged Cpp-application; at least not according to the current documentation and provided samples.

Environment: Visual Studio Community 2022 17.9.4.
This happens with the NuGet packages in the versions referenced in the sample project, but also with up-to-date packages.

Update: the x86 build works as expected.

Dominant language
PowerShell
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Forks
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Avg merge
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Merged PRs (30d)
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