Microsoft Releases .NET Core 3.1

.NET Core 3.1 has been released, Microsoft announced on Tuesday.

Described as a "small and short release," .NET Core 3.1 focuses on two of the biggest features highlighted in the release of .NET Core 3.0 earlier this fall -- Blazor (for C# Web development instead of JavaScript) and desktop development (Windows Forms and Windows Presentation Foundation).

Because Microsoft has been primarily polishing up those and other existing features in the milestone 3.0 release, version 3.1 is mostly notable for its licensing, indicated Microsoft program manager Richard Lander in the announcement.

"The most important feature is that .NET Core 3.1 is an long-term supported (LTS) release and will be supported for three years," Lander said. "As we've done in the past, we wanted to take our time before releasing the next LTS release. The extra two months (after .NET Core 3.0) allowed us to select and implement the right set of improvements over what was already a very stable base. .NET Core 3.1 is now ready to be used wherever your imagination or business need takes it."

.NET Core 3.1 is also known for Blazor, the ASP.NET Core technology that puts WebAssembly to use as a browser compilation target for higher-order programming languages so they can be used in Web development instead of JavaScript. That opens up Web development to a a whole new audience of C# jockeys who heretofore didn't want to mess with JavaScript.

In a separate post outlining what's new in ASP.NET Core 3.1, Microsoft highlighted partial class support for Razor components. "Razor components are now generated as partial classes," Microsoft said. "Code for a Razor component can be written using a code-behind file defined as a partial class rather than defining all the code for the component in a single file. For more information, see Partial class support."

While that covers the Web/Blazor side of things, the other main point of focus, desktop development, is marked by one "unfortunate breaking change" in .NET Core 3.1 resulting from the removal of Windows Forms controls -- specifically, DataGrid, ToolBar, ContextMenu, Menu, MainMenu and MenuItem. They are being replaced by newer controls that have been around for a while, but still may be in use by some developers.

"You will see build breaks if you are using the controls we removed in your applications," Microsoft said. "Also, if you open .NET Core 3.0 applications in the latest versions of the .NET Core Windows Forms designer, you will see errors if you are using these controls. We recommend you update your applications to .NET Core 3.1 and move to the alternative controls. Replacing the controls is a straight-forward process, essentially 'find and replace.'"

About the Author

David Ramel is an editor and writer for Converge360.


  • Microsoft Warns SameSite Cookie Changes Could Break Some Apps

    IT pros could face Web application issues as early as next month with the implementation of a coming SameSite Web change, which will affect how cookies are used across sites.

  • Populating a SharePoint Document Library by E-Mail, Part 1

    While Microsoft doesn't allow you to build a SharePoint Online document library using e-mail, there is a roundabout way of getting the job done using the tools that are included with Office 365. Brien shows you how.

  • Microsoft Previews New App Reporting and Consent Tools in Azure AD

    Microsoft last week described a few Azure Active Directory improvements for organizations wanting to connect their applications to Microsoft's identity and access service.

  • Free Software Foundation Asks Microsoft To Release Windows 7 Code

    The Free Software Foundation this week announced that it has established a petition demanding that Microsoft release its proprietary Windows 7 code as free software.

comments powered by Disqus

Office 365 Watch

Sign up for our newsletter.

Terms and Privacy Policy consent

I agree to this site's Privacy Policy.