Beginning Web Development, Silverlight, and ASP.NET AJAX

CHAPTER 4
Data Binding with ASP.NET
Most applications use some form of data store, with the application itself being a
means to store, retrieve, manipulate, and view data. These applications might use a SQL
Server 2005 database, a storage area network, or even a simple XML file. Web applications
are no exception, and typically these applications are termed data-driven applications.
When it comes to retrieving and representing data, a myriad of options are available; over
time, the technology has evolved dramatically. The reason for this is that the code needed
to access data and the engines that run the data itself tend to be resource heavy, and in
situations such as on the Web where they may be used in clustered environments (i.e.,
the same application running on a number of machines) and serving millions of users,
they can be expensive to maintain. As a result, the technology that developers use to create
data-driven applications has evolved rapidly, driven by the needs of scaling to large
audiences.
.NET provides a data programming technology for you to use in your applications. It
is called ADO.NET. It consists of a number of managed classes that enable your applications
to connect to data sources, execute commands, and manage disconnected data. In
this chapter, you’ll look at the architecture of ADO.NET and how it works to bring data to
your application.
You’ll look into the SQL Server 2005 Express edition, a free version of the industryleading
enterprise database software from Microsoft, as well as a sample database,
AdventureWorks, that is used to demonstrate many of its features.
You’ll wrap the chapter up with a tour through some of the server controls that can
be used to provide data awareness to your web application through data binding.
What Is ADO.NET
Scalability is typically achieved by breaking an application into functional tiers. As I mentioned
in the previous chapter, keeping state between tiers has a high cost when it comes
to scalability, performance, and security. Data-aware applications are no exception.
ASP.NET offers view state as a great alternative to maintaining control state between the
browser and server to provide both a nice programming interface and control state management
with minimum resource consumption. When writing data applications, the cost
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