Update on .NET Core 3.0 and .NET Framework 4.8

In May,we announced   .NET Core 3.0, the next major version of .NET Core that adds support for building desktop applications using WinForms, WPF, and Entity Framework 6. We also announced some exciting updates to .NET Framework which enable you to use the new modern controls from UWP in existing WinForms and WPF applications.

Today, Microsoft is sharing a bit more detail on what we’re building and the future of .NET Core and .NET Framework.

.NET Core 3.0   addresses three scenarios our .NET Framework developer community has asked for, including:

• Side-by-side versions of .NET that support WinForms and WPF:   Today there can only be one version of .NET Framework on a machine. This means that when we update .NET Framework on patch Tuesday or via updates to Windows there is a risk that a security fix, bug fix, or new API can break applications on the machine. With .NET Core, we solve this problem by allowing multiple versions of .NET Core on the same machine. Applications can be locked to one of the versions and can be moved to use a different version when ready and tested.

• Embed .NET directly into an application:   Today, since there can only be one version of .NET Framework on a machine, if you want to take advantage of the latest framework or language feature you need to install or have IT install a newer version on the machine. With .NET Core, you can ship the framework as part of your application. This enables you to take advantage of the latest version, features, and APIs without having to wait for the framework to be installed.

• Take advantage of .NET Core features:   .NET Core is the fast-moving, open source version of .NET. Its side-by-side nature enables us to quickly introduce new innovative APIs and BCL (Base Class Library) improvements without the risk of breaking compatibility. Now WinForms and WPF applications on Windows can take advantage of the latest .NET Core features, which also includes more fundamental fixes for an even better high-DPI support.

.NET Framework 4.8   addresses three scenarios our .NET Framework developer community has asked for, including:

• Modern browser and modern media controls:   Today, .NET desktop applications use Internet Explorer and Windows Media Player for showing HTML and playing media files. Since these legacy controls don’t show the latest HTML or play the latest media files, we are adding new controls that take advantage of Microsoft Edge and newer media players to support the latest standards.

• Access to touch and UWP Controls:   UWP (Universal Windows Platform) contains new controls that take advantage of the latest Windows features and touch displays. You won’t have to rewrite your applications to use these new features and controls. We are going to make them available to WinForms and WPF so that you can take advantage of these new features in your existing code.

• High DPI improvements:   The resolution of displays is steadily increasing to 4K and now even 8K resolutions. We want to make sure your existing WinForms and WPF applications can look great on these displays.

Given these updates, we’re hearing a few common questions, such as “What does this mean for the future of .NET Framework?” and “Do I have to move off .NET Framework to remain supported?” While we’ll provide detailed answers below, the key takeaway is that we will continue to move forward and support the .NET Framework, albeit at a slower pace.

How Do We Think of .NET Framework and .NET Core Moving Forward?

.NET Framework is the implementation of .NET that’s installed on over one billion machines and thus needs to remain as compatible as possible. Because of this, it moves at a slower pace than .NET Core. I mentioned above that even security and bug fixes can cause breaks in applications because applications depend on the previous behavior. We will make sure that .NET Framework always supports the latest networking protocols, security standards, and Windows features.

.NET Core is the open source, cross-platform, and fast-moving version of .NET. Because of its side-by-side nature it can take changes that we can’t risk applying back to .NET Framework. This means that .NET Core will get new APIs and language features over time that .NET Framework cannot. At Build I did a demo   showing how the file APIs were faster on .NET Core. If we put those same changes into .NET Framework we could break existing applications, and we don’t want to do that.

We will continue to make it easier to move applications to .NET Core. .NET Core 3.0 takes a huge step by adding WPF, WinForms and Entity Framework 6 support, and we will keep porting APIs and features to help close the gap and make migration easier for those who chose to do so.

If you have existing .NET Framework applications, you should not feel pressured to move to .NET Core. Both .NET Framework and .NET Core will move forward, and both will be fully supported, .NET Framework will always be a part of Windows. But moving forward they will contain somewhat different features. Even inside of Microsoft we have many large product lines that are based on .NET Framework and will remain on .NET Framework.

In conclusion, this is an amazing time to be a .NET developer. We are continuing to advance the .NET Framework with some exciting new features in 4.8 to make your desktop applications more modern. .NET Core is expanding into new areas like Desktop, IoT and Machine Learning. And we are making it easier and easier to share code between all the .NET’s with .NET Standard.

Scott Hunter, Director of Program Management for .NET

Scott Hunter works for Microsoft as a Director of Program Management for .NET. This include .NET Framework, .NET Core, Managed Languages, ASP.NET, Entity Framework and .NET tooling. Before this Scott was the CTO of several startups including Mustang Software and Starbase, where he focused on a variety of technologies – but programming the Web has always been his real passion.