Windows Forms

Windows Forms (WinForms) is a graphical (GUI) class library included as a part of Microsoft .NET Framework, providing a platform to write rich client applications for desktop, laptop, and tablet PCs. While it is seen as a replacement for the earlier and more complex C++ based Microsoft Foundation Class Library, it does not offer a comparable paradigm and only acts as a platform for the user interface tier in a multi-tier solution.

A Windows Forms application is an event-driven application supported by Microsoft's .NET Framework. Unlike a batch program, it spends most of its time simply waiting for the user to do something, such as fill in a text box or click a button.

Windows Forms provides access to native Windows User Interface Common Controls by wrapping the extant Windows API in managed code. With the help of Windows Forms, the .NET Framework provides a more comprehensive abstraction above the Win32 API than Visual Basic or MFC did.

All visual elements in the Windows Forms class library derive from the Control class. This provides a minimal functionality of a user interface element such as location, size, color, font, text, as well as common events like click and drag/drop. The Control class also has docking support to let a control rearrange its position under its parent. The Microsoft Active Accessibility support in the Control class also helps impaired users to use Windows Forms better.

Besides providing access to native Windows controls like button, textbox, checkbox and listview, Windows Forms added its own controls for ActiveX hosting, layout arrangement, validation and rich data binding. Those controls are rendered using GDI+.

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