The CData ADO.NET Provider for XML implements two ADO.NET interfaces you can use to retrieve data from XML: XMLDataAdapter and XMLDataReader objects. Whereas XMLDataAdapter objects retrieve a single result set of all the data that matches a query, XMLDataReader objects fetch data in subset increments as needed.

Using the XMLDataAdapter

Use the adapter's Fill method to retrieve data from the data source. An empty DataTable instance is passed as an argument to the Fill method. When the method returns, the DataTable instance is populated with the queried data. Note that the XMLDataAdapter is slower than the XMLDataReader because the Fill method needs to retrieve all data from the data source before returning.

The following example selects the Email and Username columns of the NorthwindOData table:

C#

string connectionString = "DataModel=Relational;URI=C:\people.xml";

using (XMLConnection connection = new XMLConnection(connectionString)) {
  XMLDataAdapter dataAdapter = new XMLDataAdapter(
  "SELECT Email, Username FROM NorthwindOData", connection);

  DataTable table = new DataTable();
  dataAdapter.Fill(table);

  Console.WriteLine("Contents of NorthwindOData.");

  foreach (DataRow row in table.Rows) {
    Console.WriteLine("{0}: {1}", row["Email"], row["Username"]);
  }
}

VB.NET

Dim connectionString As String = "DataModel=Relational;URI=C:\people.xml"

Using connection As New XMLConnection(connectionString)
  Dim dataAdapter As New XMLDataAdapter("SELECT Email, Username FROM NorthwindOData", connection)

  Dim table As New DataTable()
  dataAdapter.Fill(table)

  Console.WriteLine("Contents of NorthwindOData.")

  For Each row As DataRow In table.Rows
    Console.WriteLine("{0}: {1}", row("Email"), row("Username"))
  Next
End Using