.NET 9 Preview 3: 'I've Been Waiting 9 Years for This API!'

Microsoft's third preview of .NET 9 sees a lot of minor tweaks and fixes with no earth-shaking new functionality, but little things can be important to individual developers.

For example, who would have figured that adding the PersistableAssemblyBuilder type in System.Reflection.Emit was a big deal?

"Finally! 🎉 I've been waiting 9 years for this API! I'll try and get this working, and report back with feedback," commented a developer about that addition in a GitHub discussion announcing .NET 9 Preview 3.

More about that API -- under the .NET Libraries section -- can be found in the release notes.

Microsoft's James Montemagno summarized what's new in Libraries, Runtime and the SDK last week, with other highlights including:

Other highlights for different .NET 9 components include:

  • Entity Framework Core 9:
    • Auto-compiled models
    • Sugar for HierarchyId path generation
  • .NET MAUI:
    • Multi-target versions of .NET for iOS bindings
    • Android Asset Packs
  • ASP.NET Core:
    • Endpoint metadata on the developer exception page
    • Added InternalServerError and InternalServerError<TValue> to TypedResults
    • Handle keyboard composition events in Blazor
.NET Schedule
[Click on image for larger view.] .NET Schedule (source: Microsoft).

.NET 9, coming in November, has a special focus on cloud-native apps and performance, Microsoft said. As a standard-term support (STS) release, it will be supported for 18 months.

Complete information is summarized in the What's new in .NET 9 documentation, which was updated April 11.

About the Author

David Ramel is an editor and writer for Converge360.

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