Summary

In this chapter you have built a working application that spans three tiers. To review, you have accomplished the following:

• Created the interfaces and structures necessary to pass data across a network

• Built an object to retrieve, save, and delete data from a database

• Built an encapsulated business object that is aware of whether it has been edited

• Inherited from the CollectionBase class to build your own collection class to manage your objects

• Built a reusable form for listing records that can be printed, searched, and sorted

• Inherited from a base list form to display information from the database for your specific needs

• Built a reusable form for editing records

• Inherited from this base edit form so that you can edit your object

• Deployed your components to IIS

That is a lot of work for one chapter! However, you have also started to understand how you can build code specifically for the purpose of reusing it by creating generic routines that can adapt to the data given them (you will see more of this in Chapter 10, "Using Reflection"). You have also seen how easy it is to build and deploy all of the tiers needed for a three-tier application. In later chapters you will expand on this concepts to make your objects more robust.

In the next chapter you will see how to implement centralized error handling in an enterprise application. This goes far beyond the concepts of the Try..Catch..Finally block in that you will implement methods to inform technical support that an error has occurred at the moment that it occurs.