Dot Net North - November 2025
Take a Note of UI with .NET 10 - Peter Bull
What's New?
.NET 10 is the latest long-term or LTS release of .NET which is supported for three years which includes runtime improvements, new library APIs and support for standalone single C# file-based apps. .NET 10 includes quality enhancements to Windows Forms such as async forms plus progress with Fluent UI styles and improvements to Windows Presentation Foundation. .NET 10 also provides improved form validation for ASP.NET Core along with a reconnection UI and support for persistent component state in Blazor.
.NET 10 also brings C# 14 which adds new syntax to define extension members that allow extension properties to be defined alongside extension methods. C# 14 also enables field-backed properties where you can write a property accessor body without having to declare an explicit backing field along with C# 14 supporting null-conditional member access operators on the left side of an assignment or compound assignment. You can find out more about .NET and download the latest .NET SDK at dot.net.
Visual Studio 2026
Visual Studio 2026 is the latest version of Visual Studio that builds on the tools that developers use to make Visual Studio even more intuitive to help developers build new or scale existing solutions. Visual Studio 2026 features a refreshed and modern Fluent Design featuring updated icons and UI improvements along with increased performance that makes Visual Studio feel faster and smoother.
Visual Studio 2026 is deeply integrated with GitHub Copilot which understands your work with context across your solution, repository or tools to help developers think bigger along with offering compatibility with Visual Studio 2022 workloads and extensions to provide a future-ready IDE that is built for .NET 10 and modern development. You can find out more about Visual Studio 2026 along with where to download it at visualstudio.com.
GitHub Copilot
GitHub Copilot transforms the developer experience to provide contextual assistance throughout the software development lifecycle to enable developers to focus more on problem solving. GitHub Copilot with Agent mode can analyse code, propose edits and run tests or validate results to help create new functionality, uncover hidden bugs or help fix any mistakes.
GitHub Copilot can perform actions by leveraging a wide range and choice of tools using Model Context Protocol services or you can create a new MCP server for your needs. GitHub Copilot is integrated into Visual Studio 2026 and offers mode of controls with ask mode to control any suggested changes or agent mode to apply them. You can try GitHub Copilot yourself by visiting github.com/copilot.
.NET first-party UI technologies
ASP.NET Core Web API
The A to (almost) Z of first-party UI in .NET and how Copilot helped put together an example starting with ASP.NET Core Web API, which is used to create RESTful APIs using ASP.NET Core controllers or minimal APIs which is supported on Linux, macOS and from Windows 8 and later. GitHub Copilot was used to create suitable endpoints from another application along with creating an allowed background attribute and a .http file for the API.
ASP.NET Core Web App
ASP.NET Core Web App is for an ASP.NET Core application using Model-View-Controller or Razor Pages for Linux, macOS, Windows 8 or later and GitHub Copilot was used in an updated example to add code to keep a modal open if the model state was not valid.
Blazor Web App & Blazor WebAssembly App
Blazor Web App is for creating a Blazor web app supporting server-side rendering and client interactivity for Linux, MacOS and Windows 10 or later where GitHub Copilot was used in an updated example to update a modal to support edit and new. Blazor WebAssembly is for web apps with rich dynamic user interfaces for modern browsers such as Safari, Chrome, Firefox and Microsoft Edge where GitHub Copilot was used to create a local storage-based notes provider using Blazored Local Storage in a copy of the Blazor Web App.
Console App
Console App is a command line application for Linux, macOS and Windows from Windows 7 and later which can be provided with command-line arguments or offer interactivity where GitHub Copilot was used to build a Console Application based upon another example that would be driven by command line arguments by implementing a command-line argument parser and interactive mode that was updated to quit with Escape key and ask to confirm before deleting.
Class Library
Class Library is a reusable collection of classes, interfaces and methods although not a UI technology it is where the common functionality for the demo is defined, and GitHub Copilot was used to update the Class Library from an older demo to add required attributes for one of the UI technologies to be covered.
Local MCP Server Console App
Local MCP Server Console app is for implementing tools in a local Model Context protocol server from a command-line application for Linux, macOS and Windows 11 where GitHub Copilot was used as the UI technology to surface the MCP server as well as create the tool for notes based upon the Class Library Functionality.
.NET MAUI App
.NET MAUI app is a cross-platform UI technology using XAML for UI and C# for logic supporting iOS, Android, Mac Catalyst and WinUI for Windows 10 and Windows 11 with GitHub Copilot used to update an old demo including updating a Note Control to be scalable and for latest changes to the popup in the .NET MAUI Community Toolkit.
UWP App
UWP app is a Universal Windows Platform app using .NET and Native AoT to aid in modernising legacy .NET native UWP applications using XAML for Windows 10 and Windows 11. GitHub Copilot was used to create a UWP app from a note app in another project along with to create relay command, view model and converters for note and content models due to UWP differences and to create a HTML to Windows colour converter and was the project that required updates to Class Library to support AoT or Ahead of Time compilation.
Windows Forms App & Windows Forms Notify Icon
Windows Form app is the UI technology for native Windows apps which began with the release of the original .NET Framework and supports Windows 7 to Windows 11. GitHub Copilot was used to create this from a note app in another project including creating a note control for Windows Forms but the folded corner was on the top right and was prompted to move this to the bottom right. Windows Forms Notify Icon allows a Windows Forms app to be used from the notification area or task tray in Windows 7 or later where GitHub Copilot was used to create the Notification Tray implementation and updated to add an option to exit and so it loads when the Windows Forms application is closed.
WPF Application
WPF application uses the technology of Windows Presentation with XAML for UI and C# for logic to create apps for Windows 7 or later with GitHub Copilot used to create a note control based upon another note app.
WinUI App & Windows Widget
WinUI app is for creating modern native Windows 10 and Windows 11 apps using WinUI with XAML and C# with Windows App SDK supporting MSIX for side-loading or distribution via the Microsoft Store. GitHub Copilot was used to create apps for Console, UWP and Windows Forms based on this app and the Note Control for the WPF app along with being used to add the titlebar supported in Windows App SDK in the WinUI app. Windows Widget is the final first-party UI technology using Adaptive Cards to show Widgets in the Widgets Board in Windows 11 by creating a Widget Provider in a WinUI app using Windows App SDK. GitHub Copilot was used to create the Adaptive Cards for configuration with new and refresh at the top and a list with three Notes with Edit and Delete buttons with Paging at the bottom. GitHub Copilot was also used to create a Confirmation Adaptive Card based on the confirmation flow from the WinUI app, create an Adaptive Card for creating or editing notes and to create a service for configuration that would support the paging notes.
NuGet
NuGet packages such as Comentsys.Toolkit include useful functionality such as SVG-based assets along with common data binding for XAML-based apps. Comentsys.Toolkit.WindowsAppSdk extends Comentsys.Toookit including support for creating Widget Providers in WinUI apps using Windows App SDK. ModernWpfUI provides additional modern styles and features such as CommandBar and Content Dialog for Windows Presentation Foundation apps and CommunityToolkit.Maui for .NET MAUI Community Toolkit includes a collection of features such as popup for presenting information in apps. You can find these packages for .NET along with many others at nuget.org.
.NET Third-party UI technologies
.NET also has third-party UI technologies to help bring .NET apps cross-platform or to the browser using C# or XAML based on WinUI, Windows Presentation Foundation or even Silverlight. Uno Platform is a free open-source platform for building cross-platform native mobile, web, desktop and embedded apps in .NET using C# or a modern WinUI 3-based XAML syntax. AvaloniaUI is an open-source UI framework to create multi-platform apps with .NET for desktop, mobile, web and browser using XAML based on Windows Presentation Foundation. OpenSilver is an open-source plugin-free framework for apps with .NET that run in any browser or device using XAML based on Silverlight or Windows Presentation Foundation.
Summary
.NET 10 allows you to create cloud and web apps with ASP.NET Core Web API or ASP.NET Core Web App and build Blazor apps for server or client using WebAssembly. .NET 10 also enables you to craft Console App including local Model Context Protocol Servers or contain any common app functionality with Class Libraries. .NET 10 supports making cross-platform mobile and desktop apps with a single project using .NET MAUI or define Windows desktop apps using UWP or WPF along with facilitating WinForms apps that can use the Notification Area or WinUI apps with Windows App SDK that can provide a Windows Widget. You can find the demo showing off all the first-party UI technologies in .NET 10 along with slides at github.com/RoguePlanetoid/takeanoteofuiwithdotnet10.