Chapter 4: Data Readers, Command Objects, and Web Server Controls

Chapter 4 - Data Readers, Command Objects, and Web Server Controls
byJohn Kauffman, Fabio Claudio Ferracchiatiet al.?
Wrox Press ?2002

Overview

Having spent the last chapter focusing on how to connect to different data stores, we now need to look more carefully at our options for reading data, and displaying it on a web page. As you now know, ADO.NET has two kinds of object for bringing data in through a connection: data reader classes, and the DataSet class. Once you've retrieved the data, ADO.NET offers numerous presentation options.

In this chapter, we'll start with a comparison of the two approaches to working with data. After that, we'll focus on data readers (leaving DataSet for the previous chapter concerning the DataGrid, a powerful, flexible, yet easy-to-use tool for displaying data on an ASP.NET page. The running order looks something like this:

• The basic theory of reading and displaying information

• A comparison of data reader objects and the DataSet object

• An introduction to ADO.NET command objects

• ADO.NET data reader objects

• Four data controls that display multiple values:

  • List boxes and drop-down list boxes

  • Groups of radio (option) buttons

  • Multiple selection controls, including check boxes and list boxes

  • The ASP.NET DataGrid, and some basic formatting