ASP.NET 4 Unleashed

Building a SQL Hierarchical Data Source Control

In this final section of this chapter, we build a SqlHierarchicalDataSource control. This custom control enables you to declaratively and (thus) easily bind controls such as the Menu and TreeView controls to data retrieved from a database.

Note

The code samples in this section can be found in the SqlHierarchicalDataSourceVB and SqlHierarchicalDataSourceCS applications in the accompanying source code on the book’s website.

The page in Listing 22.32 illustrates how you can use the SqlHierarchicalDataSource control to bind a Menu control to a database table that contains nested categories.

Listing 22.32. ShowMenu.aspx

When you open the page in Listing 22.32, all the rows from the Categories ...