Developing a Composite Windows Forms Control
You can develop a composite Windows Forms control by combining other Windows Forms controls. Composite controls that derive from System.Windows.Forms.UserControl are called user controls. The base class, UserControl, provides keyboard routing for the child controls, thus ensuring that child controls can receive focus. The Windows Forms designer in Microsoft Visual Studio .NET provides rich design-time support for authoring user controls. For an example of a user control, see the UserControl sample in .NET Samples – Windows Forms: Control Authoring.