CDO & MAPI Programming with Visual Basic:

Chapter 5. Collaboration Data Objects

Collaboration Data Objects (CDO) are the modern way for Visual Basic programmers to create professional, messaging-enabled applications. CDO provides a rich interface to the messaging API in the form of an object model—a programming concept that should be especially familiar to Visual Basic programmers. An object model is a (programming) language-independent way for programs to expose objects to other programs. One object model that you may be familiar with is ActiveX Data Objects (ADO), for accessing data in OLE DB data sources. You may also have used Visual Basic to control another application (such as Microsoft Word) through Automation. This is another example of using an object model.

CDO is the focus of the remainder of this book. This chapter emphasizes a strong understanding of fundamental CDO concepts, including discussion of Microsoft’s Component Object Model (COM) and the benefit of using software components versus writing applications from scratch. This leads to a discussion of object models in general and the CDO object model in particular. The general discussion of COM and object models is included here because a firm understanding of these topics leads to a much better understanding of how the CDO object model works and how it relates to MAPI. Developers who have a very strong understanding of COM and of object models can safely skip the first two sections of this chapter. For developers who do not have a firm grasp of COM, ...