.NET Conf 2024 is bringing a wave of excitement, particularly for desktop developers working with Windows Presentation Foundation (WPF) and Windows Forms (WinForms). With the release of .NET 9, Microsoft is introducing significant updates to these frameworks, making it easier to bring a modern, sleek, and accessible experience to desktop applications. Here’s a breakdown of what’s new and how these improvements can bring a fresh look and enhanced functionality to your WPF and WinForms applications.

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WPF: Bringing Windows 11 Aesthetics to Your Desktop Apps

WPF has long been the go-to for developers seeking a high-performance, versatile desktop app experience. As part of .NET 9, Microsoft is introducing substantial updates to bring WPF apps up to modern design standards, aligning closely with Windows 11’s look and feel.

Key Enhancements:

1. Light and Dark Theme Support: Apps can now respond to system theme settings, making it easy for users to switch between light and dark modes seamlessly.
2. Rounded Corners and Accent Colors: In line with Windows 11 design guidelines, controls now feature rounded corners and respond to system accent colors, giving apps a modern, polished appearance.
3. The Fluent Theme: One of the most exciting additions is the new Fluent theme, which brings a fresh Windows 11 aesthetic to WPF apps, incorporating light and dark mode, system accent color, and refined typography for a contemporary look and feel.
4. Hyphen-Based Ligature Support: Responding to community feedback, .NET 9 now includes support for hyphen-based ligatures in WPF. This improvement ensures better text rendering and improved readability, helping developers create polished and accessible text-based interfaces.

The new Fluent theme was showcased at Build 2024 and is now generally available, adding a modern edge to WPF apps running on Windows 10, Windows 11, and Windows Server 2019.

WPF Gallery App: A Hands-On Demo Tool

To demonstrate the power of these updates, Microsoft has released the WPF Gallery App, a sample tool that allows developers to see WPF controls and styles in action under .NET 9. It showcases the new Fluent theme in both light and dark modes, providing a valuable reference for anyone looking to incorporate these elements into their own projects. The source code is freely available on GitHub, allowing developers to explore and adapt the code for their needs.

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WinForms: Modernizing Legacy Applications with New Capabilities

While WPF has brought high-performance graphics to desktop applications, WinForms remains a favorite in the enterprise space, particularly for line-of-business applications. With the .NET 9 release, WinForms is now equipped with several long-awaited updates, blending the simplicity of WinForms with the power of modern .NET capabilities.

Key Enhancements:

1. Modernized Codebase: Thousands of lines of WinForms code have been optimized to leverage the latest C# capabilities, ensuring improved performance and maintainability.
2. Updated Controls: Enhancements include multi-select support for the FolderBrowserDialog and click-through capabilities for the ToolStrip control, which streamline usability and enhance control behavior.
3. Dark Mode Detection (Experimental): Responding to popular demand, WinForms now includes a dark mode detection feature, enabling developers to automatically apply dark mode styling if the system is in dark mode—a significant step for providing a consistent user experience across applications.
4. Async Capabilities with Control.InvokeAsync: The new Control.InvokeAsync API is a game-changer, allowing developers to leverage async operations within WinForms more easily. With this capability, WinForms apps can now integrate with Web APIs, AI, and the Semantic Kernel, enabling sophisticated workflows and data processing capabilities that were previously challenging to implement in synchronous environments.

These updates empower WinForms developers to create versatile, modern applications while still supporting legacy systems. This is particularly important for organizations looking to modernize their existing line-of-business applications without needing to rewrite them from scratch.

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Building the Next Generation of Desktop Apps

The enhancements in WPF and WinForms with .NET 9 mark a significant step forward in desktop application development. By incorporating modern UI elements, updated controls, and async capabilities, Microsoft continues to bridge the gap between traditional desktop apps and the requirements of today’s advanced, connected experiences.

For developers, this means having the best of both worlds: the ability to maintain and enhance existing applications while adopting modern technologies and practices that keep their apps looking fresh and running smoothly. Whether you’re building new applications or modernizing existing ones, the .NET 9 updates provide the tools to create visually engaging, responsive, and accessible desktop applications that meet the needs of today’s users.

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With .NET 9, Microsoft is reaffirming its commitment to the desktop developer community. The updates that would be showcased at .NET Conf 2024 are proof of how WPF and WinForms remain powerful frameworks in the modern software development landscape, allowing developers to craft user experiences that feel right at home on Windows 10 and Windows 11.

As desktop development continues to evolve, now is an exciting time to dive into these frameworks, explore the new Fluent theme, and leverage async programming in your WinForms applications. The future of desktop apps is here, and it’s looking brighter—and sleeker—than ever.