ADO.NET in a Nutshell

Creating a Strongly Typed DataSet

There are three ways a strongly typed DataSet class can be generated. The easiest method is to drop one or more DataAdapter objects from the Data tab in the Visual Studio .NET Toolbox onto a design surface such as a form or a component. Configure each DataAdapter to select data from one table. Right-click on the design surface and select Generate DataSet. Provide a name for the DataSet, select the tables to be included, and generate the new strongly typed DataSet. To relate the two tables, double-click on the XSD file for the new DataSet in the Solution Explorer window to open it. Right-click on the child table in XSD schema designer, select Add/New Relation... from the shortcut menu, and complete the dialog. Instances of the strongly typed DataSet can now be created programmatically or by using the DataSet object from the Data tab in the Visual Studio.NET Toolbox.

The other two methods are more involved, and both require an XSD schema file, which can be generated in a number of ways, e.g., using Visual Studio IDE tools, third-party tools, or the DataSet WriteXmlSchema( ) method. The following example shows a utility that uses the WriteXmlSchema( ) method to create an XSD schema based on the Categories and Products tables in the Northwind database:

String connString = "Data Source=localhost;" + "Initial Catalog=Northwind;Integrated Security=SSPI"; SqlDataAdapter daCategories = new SqlDataAdapter( "SELECT * FROM Categories", connString); SqlDataAdapter ...