.NET 11 Preview 6: C#, ASP.NET Core, MAUI & EF Core Advancements

Deep Dive into .NET 11 Preview 6

Microsoft's .NET 11 Preview 6 release showcases a mature development cycle with substantial feature additions across its core ecosystem. The integration of extension indexers in C# is a particularly welcome enhancement, completing the previously introduced extension members functionality and offering developers more expressive ways to interact with existing types. The advancement of union types, now with compiler and serialization support, is a significant step towards more robust and concise code, especially for scenarios involving state management or discriminated unions. For web developers, the improvements in ASP.NET Core are noteworthy. The end-to-end support for asynchronous validators in Minimal APIs, coupled with automatic rejection of unsafe cross-origin requests, significantly bolsters security and developer productivity. Blazor's enhanced Virtualize component and server-side configuration for client startup behavior further refine the user experience and development workflow. The integration of YARP into the Blazor Gateway also simplifies cross-origin scenarios for standalone WebAssembly apps.

From a cross-platform perspective, .NET MAUI's progress is evident with the Windows CollectionView leveraging WinUI's ItemsRepeater and the re-implementation of Shell on Android using standard handlers, signifying a move towards a more unified and performant architecture. The deprecation of the Microsoft.Maui.Controls.Compatibility package is a crucial breaking change that developers must be aware of, emphasizing the ongoing evolution and modernization of the framework. Entity Framework Core's translation of FullJoin and enhanced support for complex type properties in keys and indexes are valuable additions for data modeling and querying. The Azure Cosmos DB provider's index configuration options and SQLite's built-in encryption further enhance data management capabilities. The extensive list of runtime and performance improvements, including JIT enhancements and faster NativeAOT interface dispatch, underscores Microsoft's commitment to optimizing the .NET platform for a wide range of applications.

While the preview nature of some features, like union types, means they require specific language versions and might not be production-ready, the direction is clear and promising. The primary limitation is the inherent risk associated with adopting preview features, which can undergo changes before the final release. Developers need to carefully evaluate the stability and long-term implications of integrating these preview functionalities into their projects. However, for those on the bleeding edge of .NET development, these previews offer a compelling glimpse into the future and an opportunity to provide early feedback.

Key Points

• C# now supports extension indexers, completing the extension members feature.
• Union types have compiler and System.Text.Json serialization support, simplifying their use.
• ASP.NET Core Minimal APIs gain end-to-end asynchronous validator support.
• Unsafe cross-origin requests are automatically rejected by default in ASP.NET Core.
• Blazor's Virtualize component can now open at a chosen item and scroll on demand.
• Blazor Gateway uses YARP for built-in reverse proxying, simplifying CORS.
• .NET MAUI's CollectionView is now available on Windows using WinUI's ItemsRepeater.
• Microsoft.Maui.Controls.Compatibility package is no longer supported, a breaking change.
• Entity Framework Core adds FullJoin operator translation and improved complex type property support for keys/indexes.
• Azure Cosmos DB provider and Microsoft.Data.Sqlite receive enhancements for indexing and encryption, respectively.
• Significant performance improvements are noted across the runtime, including JIT and NativeAOT.

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📖 Source: Microsoft Releases .NET 11 Preview 6 With Language and Framework Updates