WPF hot reload builds on C# hot reload model
The same edit-and-save workflow that applies to C# code now works for XAML markup and UI changes.
JetBrains' IDE now lets developers modify WPF applications without rebuilding, speeding up the edit-test cycle.
The same edit-and-save workflow that applies to C# code now works for XAML markup and UI changes.
WPF hot reload lets developers modify XAML in Rider and see the changes while the application is running. When a file is saved with Ctrl+S, changes apply automatically to the live application without rebuilding. Text, buttons, and other UI elements update in real time. The Windows application window reflects changes instantly, keeping the running state intact.
Pasting a XAML snippet into the editor and saving triggers an immediate update in the running application. A StackPanel containing text and a button was added through a code snippet and appeared in the application window without any rebuild or restart. The live application updated automatically to include both the text element and the button, visible on the Windows application in real time.
Style properties like font size can be modified and take effect immediately in the running application. Increasing the font size of text makes it more readable without requiring a restart or rebuild.
WPF hot reload is not limited to visual properties. Developers can add click handlers to XAML elements and modify the underlying application logic and behavior. Method auto-completion is available for event handlers, making it easy to wire up new interactions. Logic changes are applied alongside markup changes, so both the UI structure and its behavior can evolve without stopping the application.
This allows developers to use modern .NET features while benefiting from live code changes.
Breakpoints set in newly added code paths remain active during WPF hot reload. After using the C# hot reload button to apply changes, the debugger becomes active when the modified code is triggered. This allows developers to step through the execution, inspect variables, and control the program flow without restarting the application. The breakpoint becomes functional once the hot reload is applied, enabling immediate debugging of new event handlers and logic.
After hot reload applies code changes, saving the XAML file with Ctrl+S activates newly added event handlers. A button click event was added via hot reload and immediately became responsive, triggering a .NET 10 message box without requiring an application restart. When the message box button (such as Retry) was clicked, it triggered the previously set breakpoint, allowing the developer to inspect the application state.
WPF hot reload is available in Rider 2026.2 as part of the dotUltimate suite.
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