winforms

Windows Forms (WinForms) is a framework for building desktop applications that run on Windows. It has been part of Microsoft's .NET development platform since 2002, making it one of the older UI toolkits still in active use. The framework lets developers build applications with windows, buttons, text boxes, and other visual controls by dragging and dropping them in a visual editor inside Visual Studio, which makes building straightforward business applications relatively quick.

This repository contains the open-source version of WinForms that runs on modern .NET (version 6 and later). It is a fork of the original code that was part of the older .NET Framework, updated and maintained by Microsoft. The two versions have diverged over time, so code written for the old framework may need adjustments to work here. The repository does not include the WinForms visual designer built into Visual Studio, just the runtime framework itself.

The project's stated purpose is to remain a practical tool for building stable, complex business applications on Windows, particularly for developers who need to maintain or extend existing WinForms applications. Microsoft is not trying to add features that overlap with newer Windows UI frameworks like WPF or WinUI. Instead, updates focus on security fixes, accessibility improvements, support for high-resolution displays, and keeping up with changes in Windows itself.

About 20% of WinForms developers use Visual Basic instead of C#, and the project notes that VB-specific changes are welcomed for genuine bugs but have lower priority for code cleanup work. Contributions are open, and the README links to a developer guide explaining how to build and test the codebase locally. This is primarily relevant to C# or VB developers maintaining or building Windows desktop software.