Therefore, this article (part three) deals with using the business objects in a web application. NET controls like the Grid View in conjunction with the business objects.You'll see how you can build pages that allow you to list, create, edit and delete your contact persons and their contact data, like e-mail addresses and phone numbers.Besides the forementioned SQL scripts and database, the download also contains the full source for the demo application in C#.Before we dig into the code for the web site, let's briefly recap the application's design I showed you in the two previous articles. - I have written a new series on N-Layer design as a major follow up to this one. Part one dealt with the design of the application: what business objects do you need to fulfill the requirements of the application. The target audience for this series are developers that are ready to make the switch from using controls with custom business objects. NET 2 and C# is necessary while some knowledge about object oriented design certainly helps.The biggest drawback of storing binary data as a physical file is that your database easily can lose track of the binary data.Say, for example, you have a column that stores URLs of product images.
The entire series (including this current article) can be found here: The article uses a SQL Server 2005 Express database which is easy to use in development scenarios.Part two showed you how to code the classes that were designed in part one.You saw how to implement the data access methods and database code and how the various classes were able to work together.Storing BLOBs directly inside SQL server provides the following advantages: In summary, depending on the application being developed, you should decide whether storing BLOB data in SQL Server is the way to go. To read BLOB data, you need to use the Sql Data Reader class of ADO. The use of Sql Data Reader class to read BLOB data can be best understood with an example.That said, generally CMS systems, photo albums, slide show applications, document management systems, and so forth are good candidates for storing BLOBs inside SQL Server. You will develop a simple application that manages photos stored in a SQL Server database.
In the middle of the diagram, you see the Business Logic Layer; the bridge between the web site and the data access layer.