Chapter 6 - Control Design Concepts

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IN THIS CHAPTER

• Control Design

• Control Internals

• A Preview of the OutlookBar Control

Building quality custom controls requires knowledge and practice. During the development process, there is a time of discovery. This discovery process includes learning the underlying system, the framework, and the most practical design for the control in order to provide a clear strategy for moving the project forward. To grow knowledge, there must be a starting point from which to begin. The Windows Forms base class library can be used as such a starting point.

By studying the current set of controls and their associated designers and UITypeEditors (see Chapter 5, "Advanced Control Development," for more information on UITypeEditors), you can glean lessons and apply them to new endeavors.

Before this chapter delves into designing and building the OutlookBar control, its subcomponents, and related designers, a tour of the existing set of Windows Forms controls will provide some insight that can be applied to the construction of the OutlookBar control to be built in chapters 7, 8 and 9.

It is necessary to understand how the common controls shipped with VS .NET are constructed so that the principles behind their design and implementation can be applied to new custom controls. The remainder of this chapter is spent exploring the concepts behind the implementation of the current common controls. In addition, we explore how to use the current set of controls to gain a better understanding of how to create custom controls.