ASP.NET 4 Unleashed

Introduction to the QueryExtender Control

When you retrieve data through a data source control, you traditionally sacrifice the fine-grained control over the query in exchange for the declarative (often design-surface friendly) simplicity of the data source control. The QueryExtender control aims to give you back some of that control while still giving you all the benefits of a declarative data source.

The QueryExtender control gives you the ability to specify filter criteria, sorting options, and even custom queries written in LINQ all in a declarative fashion using a suite of nested child controls that derive from the ParameterDataSourceExpression class. The next section of this chapter provides an overview of the various types of filtering, ...