Designing Active Server Pages

Chapter 7. Using Components

One of the most powerful features of ASP is its tight integration with COM. Due to this relationship, Active Server Pages can easily use COM objects, thereby extending the feature set of ASP. Microsoft provides several ready-to-use COM objects with IIS, which will be the focus of this chapter; however, there is an entire market of third-party COM objects created by companies independent from Microsoft, which will be discussed in length in the next chapter. Furthermore, you, the developer, can create your own custom COM objects for use in your ASP projects, which we’ll touch upon briefly in this chapter.

Being able to use COM objects in ASP pages—be it Microsoft-created, third-party-created, or custom-built—is what gives Active Server Pages their great flexibility. Without the ability to use COM objects, ASP would be painfully limited in its scope. After all, ASP only provides a handful of intrinsic objects for the developer to use. These built-in ASP objects don’t grant the developer much more than the ability to read from the HTTP request stream, write to the HTTP response stream, and gather information about the web server. To extend ASP, components must be used.

To fully understand the importance of being able to use COM components in an ASP page, imagine for a moment that suddenly, ASP’s ability to use COM objects is taken away. Since ADO is nothing more than a collection of Microsoft-provided COM components that aid in database interactions, if an ...