Within the Visual Studio .NET Forms Designer, controls can be placed on the surface of any container object, such as Windows Forms, or controls such as Panel, GroupBox, or TabControl. You also can add controls to a form programmatically.
When creating controls programmatically, you must remember to associate them with a parent container control. If you don't do this, controls will be created but not displayed.
Within the Forms Designer interface, you can drag and drop controls from the toolbox or using the View menu. Figure 2.10 shows this toolbox.