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ADO.NET: Read and Write XML

ADO.NET and DataSet can read and write XML schema and XML. For more information, see How do I...Use XML and the DataSet?

Schemas, or the tables, columns, constraints and so forth, of a DataSet can be defined in several ways. One method is to create them using properties and methods (Tables.Add, Columns.Add, and so on). This establishes a schema within your DataSet that can be used as a container to hold data. Another way is to use the SqlDataAdapter or OleDbDataAdapter. When you use these commands, if the schema does not exist in a DataSet, it is created for you.

XML is an intrinsic element of ADO.NET. Several methods that support XML have been implemented. The GetXmlSchema method allows you to get the schema of a DataSet as an XSD schema. For example, if you load a DataSet from the database, you could get an XSD schema from it: Console.WriteLine(myDataSet.GetXmlSchema()); Console.WriteLine(myDataSet.GetXmlSchema()) Console::WriteLine(myDataSet->GetXmlSchema(););

This returns an XSD compliant XML schema for the schema in your DataSet.

XML representation is also retrieved through the GetXml method. Console.WriteLine(myDataSet.GetXml()); Console.WriteLine(myDataSet.GetXml()) Console::WriteLine(myDataSet->GetXml());

The sample below loads data from a database, and then outputs the XSD Schema and XML data.