One of the new ASP.NET controls available with ASP.NET 4 is the QueryExtender control. The
QueryExtender is designed to simplify filtering data returned from a
EntityDataSource by decoupling the filtering logic from the data source control. Using the
QueryExtender is easy–simply add a QueryExtender to the page, specify what data source control it applies to, and then define the filtering criteria. For example, when displaying product information on a web page you could use the
QueryExtender control and a few lines of markup to display only those products that are not within a certain price range and whose name or category starts with a user-specified search string.
Filtering the data returned by a
EntityDataSource control is certainly possible without the
QueryExtender; both the
EntityDataSource controls have a
Where property that can be used to specify filtering criteria. What the QueryExtender offers is a simpler means by which to filter data. This ASP.NET tutorial includes a number of demos (which can be downloaded at the end of this article) that showcase the
QueryExtender's ease of use and its powerful filtering capabilities. To read the entire article, Filtering Data Using ASP.NET 4’s QueryExtender Control, click here.