XAML.io adds “Migrate from WPF”: use an existing WPF application on the web
Paris, France – Userware today released version 0.8 of XAML.io, a free web-based IDE, adding Migrate from WPF: free, browser-based tools that bring existing Windows Presentation Foundation (WPF) programming to the web. Developers can analyze an integrated WPF application for web interaction, import a WPF project for use in a browser, or include Userware for end-to-end migration. The technology is powered by OpenSilver, an open source framework for Userware that implements WPF-style C# and XAML on the web by integrating into WebAssembly and rendering XAML as native HTML DOM objects.
To show how little the operating system changes, Userware has moved Family. Showthe advanced WPF reference system Vertigo was originally developed for Microsoft after the introduction of WPF. The result works live in the browser, with 97% of the original code unchanged, a figure measured as line-by-line differences in C# and XAML files between the original codes and the migrated codes:
Figure 1 – Screenshots of the family.Show, an enhanced WPF reference application, running as a Windows desktop application (left) and as a web application in a browser with XAML.io/OpenSilver (right). 97% of the original code is unchanged.
WPF is a mature, powerful framework for Windows desktop development, and it’s not going anywhere. What pushes teams to put these applications on the web is how they are delivered, how they are secured and how they are accessed. Today a WPF application must be installed and kept up-to-date on every user’s machine. On the web, that per-machine installation disappears: IT deploys once and sends updates to everyone with one click, so no one is left using an outdated version.
Security is also changing. The application works within the browser sandbox, the same model that organizations already trust on every website they use. Nothing is installed at the end, and the application has no static access to the user’s machine.
Access the changes again. Users can open the app on any device with a browser (desktop, tablet, or phone), and the same C#/XAML code base can also be deployed as desktop and mobile apps. And because OpenSilver interprets the interface as normal HTML instead of painting it on the canvas, the ported applications get native browser accessibility (based on standards like Section 508 and EN 301 549), text search, and integration with the rest of the web.
Migration without rewriting
The new XAML.io migration tools are designed to deliver those benefits without rewriting, and the work starts with analysis. New for free Compatibility Analyzer works with any size system. It reads the integrated application, identifies the WPF and platform APIs used by the application, and reports, feature by feature, what is working in OpenSilver today, what needs fixing, and what is blocking, in an exportable report. Application binaries are processed locally in the browser; only a consolidated list of unsupported features is sent to the Userware server for reporting.
Deliberate migration is not an AI rewrite. Rather than reproducing the code, XAML.io preserves the original C# and XAML and makes the framework support it, using only small, visible changes that the developer can review: unsupported IC# is wrapped in package directives, unsupported XAML is defined with comments, and all default editing is displayed in the IDE as a warning. The runtime warning system is advanced, flagging stuck or blocked code as the program runs, along with file and queue, and without crashing it. The collaboration layer behind the tools currently ships with 8 Roslyn parsers and 16 autocoders, and its WPF coverage continues to grow.
The app also looks the same after moving to the web. When you import, XAML.io automatically uses a WPF-looking theme so that the web version matches the desktop version; teams that find the old WPF look can switch to a modern theme and add responsive layouts to refresh the interface, without rewriting the application.
The full migration of Family.Show is published, so that anyone can test the claim instead of taking its attribution: compare the live migrated application, its source in XAML.io, and the original WPF source side by side. The ported version is also relatively light for what it is: the running application, including the entire .NET runtime, is squeezed into 8.1 MB, and because OpenSilver does not require a browser plugin, there is nothing the user can install. Served via a CDN, it loads in a few seconds on a good connection and is cached for the next visit; The runtime performance of an application of this type is tight. A short video of the end-to-end migration is in the presentation document.
“WPF is not going anywhere on the desktop. But many of these applications now need to live on the web as well. That means they are accessible from any device, updated centrally, and run inside the sandbox of the browser instead of full access to each user’s machine, with accessibility and readability that the desktop never gave them,” said Giovanni Albani, CEO of Userware. “What always made that painful was that it meant rewriting, and that’s exactly what we’re removing. We keep your original C# and XAML and make the framework support what your app already does, so you avoid regression and keep a codebase your team still understands.”
“For a serious application, the honest answer is that migration is a project, and that’s exactly what we do,” said Darshin Vyas, VP of Sales at Userware. “It starts with a free interoperability analysis and a fixed cost quote. We deliver milestones that you can integrate and test, and your team can keep working all the time. We’ve done this for over thirteen years, on over 10 million lines of business code.”
The automation tools are completely free, with no time limit or feature paywall. Compatibility Analyzer is robust for applications of any size, while in-browser source import is currently a preview Technology best suited for small to medium-sized, self-contained projects. For production deployments of any size, Userware offers paid services and support, and customers can sponsor specific WPF features they need, which are then shipped to everyone in an open source framework. That model is what supports free use. Third-party UI management suites are not yet supported in self-service tools and are handled within managed migrations. Userware’s roadmap includes WPF extensions, one-click web publishing, mobile and signed desktop publishing, and VB.NET support.
XAML.io is available now, is free to use and works in any modern browser.
