Microsoft has released .NET Community Toolkit 8.4, with support for partial properties in MVVM Toolkit source generators as well as new MVVM Toolkit diagnostic analyzers.
The update was unveiled December 12. Source code for the .NET Community Toolkit can be found on GitHub.
Partial properties now are available thanks to new C# language features in the .NET 9 SDK. MVVM Toolkit source generators now will leverage partial properties and semi-auto properties for defining observable properties. Declaring properties is now integrated with the C# language, instead of the MVVM Toolkit creating a new property and inferring its characteristics based on the annotated field. .NET Community Toolkit 8.4 also introduces 16 new diagnostics to the set of analyzers in the MVVM Toolkit, providing both general code analysis for MVVM scenarios and CsWinRT trim/AOT code analysis for UWP and WinUI 3.
In other changes and improvements, the MVVM Toolkit now includes MSBuild logic for friendly error messages when using an incorrect version of the Windows SDK package, and suggests how to fix it and which version to use. Custom diagnostic suppressions now work correctly when using custom attribute targets on [ObservableProperty] fields. More WinRT analyzers have been added for class-level attributes. And NuGet packages can be updated to the latest stable version.
.NET Community Toolkit is a collection of helpers and APIs that work for .NET developers. It is agnostic of any specific UI platform. .NET Community Toolkit 8.4 follows the August release of .NET Community Toolkit 8.3, which brought support for .NET 8 and NativeAOT.