ASP.NET Core updates in .NET 5 Preview 4

Sourabh Shirhatti [MSFT]

.NET 5 Preview 4 is now available and is ready for evaluation! .NET 5 will be a current release.

Get started

To get started with ASP.NET Core in .NET 5.0 Preview4 install the .NET 5.0 SDK.

If you’re on Windows using Visual Studio, we recommend installing the latest preview of Visual Studio 2019 16.6.

If you’re on macOS, we recommend installing the latest preview of Visual Studio 2019 for Mac 8.6.

Upgrade an existing project

To upgrade an existing ASP.NET Core 5.0 preview3 app to ASP.NET Core 5.0 preview4:

  • Update all Microsoft.AspNetCore.* package references to 5.0.0-preview.4.*.
  • Update all Microsoft.Extensions.* package references to 5.0.0-preview.4.*.

See the full list of breaking changes in ASP.NET Core 5.0.

That’s it! You should now be all set to use .NET 5 Preview 4.

What’s new?

Performance Improvements to HTTP/2

By adding support for HPack dynamic compression of HTTP/2 response headers in Kestrel, the 5.0.0-prevew4 release improves the performance of HTTP/2. For more information on how HPACK helps save bandwidth and help reduce latency, we recommend reading this excellent write-up by the team at CloudFlare.

Reduction in container image sizes

The canonical multi-stage Docker build for ASP.NET Core involves pulling both the SDK image and ASP.NET Core runtime image. By re-platting the SDK image upon the ASP.NET runtime image, we’re sharing layers between the two images. This dramatically reduces the size of the aggregate images that you pull. For more information about the size improvements and other container enhancements, check out the .NET 5 Preview 4 blog post

See the release notes for additional details and known issues.

Give feedback

We hope you enjoy this release of ASP.NET Core in .NET 5! We are eager to hear about your experiences with this latest .NET 5 release. Let us know what you think by filing issues on GitHub.

Thanks for trying out ASP.NET Core!


Discussion is closed. Login to edit/delete existing comments.

  • Gal Ratner 0

    Please bring Web Forms into .NET Core. its great technology and is more robust then Razor Pages.

    • Krystof Zacek 0

      Certainly not. Check out Blazor instead. Server Side Blazor is already production-ready and WebAssembly Blazor is in preparation. The only significant downside is lack of in-built-in quality components but there are plenties of both free and commercial ones available.

    • Dimitris Pantazopoulos 0

      Agreed. Web Forms still is the best choice for RAD web app development and it is robust and mature. I believe it can evolve and fit the contemporary web. Also, I think Microsoft is going to unify it in .NET 5.

Feedback usabilla icon