COM+ Programming with Visual Basic

Chapter 8. Writing and Debugging COM+ Code

In the last chapter you learned how to create a COM+ application and how to administer it. You also learned about some of the services COM+ offers. Now, let’s turn our attention to writing code for use in COM+ components to use those services. As I alluded to earlier, it is not really possible to develop components that work well inside COM+ and outside COM+. In order to take advantage of some of the COM+ services, you will want to code your components differently. Coding your components differently means that your component will expect the COM+ environment to exist.

To write COM+ components that interact with the COM+ environment, you must reference the COM+ Services Type Library in your project (Project → References and then select the COM+ Services Type Library from the listbox). There are a number of interfaces, classes, user-defined types, and enumerated types in the type library. In this section you will learn about only a few of the objects. You will get a better taste for the rest of the objects and interfaces in the type library as we discuss each service throughout the book.

Before you can write COM+ code, however, you must learn about the COM+ architecture.

COM+ Architecture

So far, you have learned how to manage applications at a high level through the Component Services Administration program or through code using the COM+ Administration Components. In this section, you will learn about how COM+ applications work internally. ...