Visual Basic 2012 Programmer's Reference

USING CONTROLS AND COMPONENTS

As Chapter 7 mentioned, a control is a programming entity that has a graphical component. Text boxes, labels, list boxes, check boxes, menus, and practically everything else that you see in a Windows application is a control.

A component is similar to a control, except it is not visible at run time. When you add a component to a form at design time, it appears in the component tray below the bottom of the form. You can select the component and use the Properties window to view and change its properties just as you can with a control. At run time, the component is invisible to the user, although it may display a visible object such as a menu, dialog box, or status icon.

This chapter explains controls and components in general terms. It describes different kinds of controls and components. It explains how your program can use them at design time and run time to give the user information and to allow the user to control your application. It also explains in general terms how a control’s properties, methods, and events work, and it lists some of the most useful properties, methods, and events provided by the Control class. Other controls that are derived from this class inherit those properties, methods, and events unless they are explicitly overridden.