Programming Visual Basic 2005

Chapter 4. Custom Controls

When the user clicks on the All Customers button of the Welcome page you've been building in previous chapters, a Rolodex of all the customers is displayed, as shown in Figure 4-1.

Figure 4-1. Complete Customer Rolodex

Unfortunately, Microsoft neglected to include a Rolodex control in Visual Studio 2005. No problem, though; in this chapter, you'll implement your own as a custom control.

Tip

This code builds on the project started in the previous chapter. You can download the source code completed in Chapter 3 if you would like to start here.

Custom Controls

Custom controls come in three flavors:

A derived control

With a derived control, you take an existing control (e.g., a button) and give it new capabilities. For example, you might create a button that knows how many times it has been clicked.

A composite control

In a composite control, you take existing controls (whether provided by the Framework, or ones you've created) and you package them together into a single control.

A from-scratch control

Creating a custom control from scratch requires that you draw the control yourself using the GDI+ capabilities covered in the next chapter.