OpenSilver 2.1 has been released, continuing the development of the Silverlight platform. This project allows users to create interactive web applications using C#, F#, XAML, and .Net. While Silverlight applications compiled with OpenSilver can now work on any desktop and mobile browsers with WebAssembly support, the compilation process is currently limited to Windows using the Visual Studio environment. The project’s code is written in C# and is available on GitHub under the MIT license.
In 2021, Microsoft ceased further development and support for the Silverlight platform, opting to focus on standard web technologies instead. Originally, the Opensilver project aimed to provide tools for extending the lifespan of existing Silverlight applications in light of Microsoft’s decision and the discontinuation of plugin support in web browsers. Opensilver fully supports the core capabilities of the Silverlight engine, including C# and XAML languages, as well as numerous platform APIs required by popular libraries such as Telerik UI, WCF Ria Services, Prism, and Mef.
Opensilver has now evolved beyond its initial purpose of extending Silverlight’s lifespan and has become a standalone platform for creating new applications. It offers a development environment (an extension for Visual Studio), support for newer versions of C# and the .NET platform, and compatibility with JavaScript libraries.
The project leverages open-source projects such as Mono, Mono-wasm, and Microsoft Blazor (part of ASP.NET Core) for executing applications in browsers through WebAssembly compilation. Opensilver also continues to work on cshtml5, which enables the compilation of C#/XAML/.NET applications into JavaScript representations suitable for browser deployment. The project’s objective is to expand the codebase with additional capabilities based on C#/XAML/.NET in WebAssembly rather than JavaScript.
The key improvements in OpenSilver 2.1 are as follows: