You can access the same column information about the results of a query that you can for table schemas. See Columns for the columns returned.

Retrieving Result Set Metadata

You can use the GetSchemaTable method of the xBaseDataReader to retrieve result set metadata. Call GetSchemaTable after calling ExecuteReader.

Each row of the DataTable describes a column in the query's result.

C#

string connectionString = "Data Source=C:\\MyData;";

using (xBaseConnection conn = new xBaseConnection(connectionString)) {
  xBaseCommand cmd = new xBaseCommand("SELECT * FROM Orders WHERE ShipCountry = 'USA'", conn);
  xBaseDataReader rdr = cmd.ExecuteReader();
  DataTable schemaTable = rdr.GetSchemaTable();
  foreach (DataRow row in schemaTable.Rows) {
    foreach (DataColumn col in schemaTable.Columns) {
      Console.WriteLine("{0}: {1}", col.ColumnName, row[col]);
    }
  }
}

VB.NET

Dim connectionString As String = "Data Source=C:\\MyData;"

Using conn As New xBaseConnection(connectionString)
  Dim cmd As New xBaseCommand("SELECT * FROM Orders WHERE ShipCountry = 'USA'", conn)
  Dim rdr As xBaseDataReader = cmd.ExecuteReader()
  Dim schemaTable As DataTable = rdr.GetSchemaTable()
  For Each row As DataRow In schemaTable.Rows
    For Each col As DataColumn In schemaTable.Columns
      Console.WriteLine("{0}: {1}", col.ColumnName, row(col))
    Next
  Next
End Using