private void DemonstrateMergeTableAddSchema ( ) {
   // create a DataSet with one table, two columns, and three rows.
   DataSet ds = new DataSet ( "myDataSet" );
   DataTable tbl = new DataTable ( "Items" );
   DataColumn c1 = new DataColumn ( "id", Type.GetType ( "System.Int32" ),"" );
   c1.AutoIncrement = true;
   DataColumn c2 = new DataColumn ( "Item", Type.GetType ( "System.Int32" ),"" );
   // dataColumn array to set primary key.
   DataColumn [ ] keyCol = new DataColumn [ 1 ];
   DataRow row;
   // add RowChanged event handler for the table.
   tbl.RowChanged+ = new DataRowChangeEventHandler ( Row_Changed );
   ds.Tables.Add ( tbl );
   tbl.Columns.Add ( c1 );
   tbl.Columns.Add ( c2 );
   // set primary key column.
   keyCol [ 0 ] = c1;
   tbl.PrimaryKey = keyCol;
   // add ten rows.
   for ( int i = 0; i <10; i++ ) {
      row = tbl.NewRow ( );
      row [ "Item" ] = i;
      tbl.Rows.Add ( row );
  }
   // accept changes.
   ds.AcceptChanges ( );
   PrintValues ( ds, "Original values" );
   // create a second DataTable identical to the first, with one extra column.
   DataTable t2 = new DataTable ( "Items" );
   // add two columns.
   DataColumn col3 = new DataColumn ( "id", Type.GetType ( "System.Int32" ) );
   DataColumn col4 = new DataColumn ( "item", Type.GetType ( "System.Int32" ) );
   DataColumn col5 = new DataColumn ( "extra",Type.GetType ( "System.String" ) );
   t2.Columns.Add ( col3 );
   t2.Columns.Add ( col4 );
   t2.Columns.Add ( col5 );
   // set primary key column.
   DataColumn [ ] t2KeyCol = new DataColumn [ 1 ];
   t2KeyCol [ 0 ] = col3;
   t2.PrimaryKey = t2KeyCol;
   // add two rows. Note that the id column must be unique.
   DataRow newRow;
   newRow = t2.NewRow ( );
   newRow [ "id" ] = 12;
   newRow [ "Item" ] = 555;
   newRow [ "extra" ] = "extra Column 1";
   t2.Rows.Add ( newRow );

   newRow = t2.NewRow ( );
   newRow [ "id" ] = 13;
   newRow [ "Item" ] = 665;
   newRow [ "extra" ] = "extra Column 2";
   t2.Rows.Add ( newRow );
   // merge the table into the DataSet.
   Response.Write ( "Merging" );
   ds.Merge ( t2,false,MissingSchemaAction.Add );
   PrintValues ( ds, "Merged With Table, Schema Added" );
}

private void Row_Changed ( object sender, DataRowChangeEventArgs e ) {
   Response.Write ( "Row Changed " + e.Action.ToString ( ) + "\tbl" + e.Row.ItemArray [ 0 ] );
}

private void PrintValues ( DataSet ds, string label ) {
   Response.Write ( "<br>" + label );

   foreach ( DataTable tbl in ds.Tables ) {
      Response.Write ( "TableName: " + tbl.TableName );

      foreach ( DataRow row in tbl.Rows ) {

         foreach ( DataColumn col in tbl.Columns ) {
            Response.Write ( "\t " + row [ col ] );
        }
         Response.Write ( );
     }
   }
}

Private Sub DemonstrateMergeTableAddSchema ( )
   ' create a DataSet with one table, two columns, and three rows.
   Dim ds As New DataSet ( "myDataSet" )
   Dim tbl As New DataTable ( "Items" )
   Dim c1 As New DataColumn ( "id", Type.GetType ( "System.Int32" ), "" )
   c1.AutoIncrement = True
   Dim c2 As New DataColumn ( "Item", Type.GetType ( "System.Int32" ), "" )
   ' dataColumn array to set primary key.
   Dim keyCol ( 1 ) As DataColumn
   Dim row As DataRow
   ' add RowChanged event handler for the table.
   AddHandler tbl.RowChanged, AddressOf Row_Changed
   ds.Tables.Add ( tbl )
   tbl.Columns.Add ( c1 )
   tbl.Columns.Add ( c2 )
   ' set primary key column.
   keyCol ( 0 ) = c1
   tbl.PrimaryKey = keyCol
   ' add ten rows.
   Dim i As Integer
   For i = 0 To 9
      row = tbl.NewRow ( )
      Row ( "Item" ) = i
      tbl.Rows.Add ( row )
   Next i
   ' accept changes.
   ds.AcceptChanges ( )
   PrintValues ( ds, "Original values" )
   ' create a second DataTable identical to the first, with
   ' one extra column.
   Dim t2 As New DataTable ( "Items" )
   ' add two columns.
   Dim col3 As New DataColumn ( "id", Type.GetType ( "System.Int32" ) )
   Dim col4 As New DataColumn ( "item", Type.GetType ( "System.Int32" ) )
   Dim col5 As New DataColumn ( "extra", Type.GetType ( "System.String" ) )
   t2.Columns.Add ( col3 )
   t2.Columns.Add ( col4 )
   t2.Columns.Add ( col5 )
   ' set primary key column.
   Dim t2KeyCol ( 1 ) As DataColumn
   t2KeyCol ( 0 ) = col3
   t2.PrimaryKey = t2KeyCol
   ' add two rows. Note that the id column can not be the
   ' same as existing rows in the DataSet table.
   Dim newRow As DataRow
   newRow = t2.NewRow ( )
   newRow ( "id" ) = 12
   newRow ( "Item" ) = 555
   newRow ( "extra" ) = "extra Column 1"
   t2.Rows.Add ( newRow )

   newRow = t2.NewRow ( )
   newRow ( "id" ) = 13
   newRow ( "Item" ) = 665
   newRow ( "extra" ) = "extra Column 2"
   t2.Rows.Add ( newRow )
   ' merge the table into the DataSet.
   Response.Write ( "Merging" )
   ds.Merge ( t2, False, MissingSchemaAction.Add )
   PrintValues ( ds, "Merged With Table, Schema Added" )
End Sub

Private Sub Row_Changed ( sender As Object, e As DataRowChangeEventArgs )
   Response.Write ( "Row Changed " + e.Action.ToString ( ) _
      + ControlChars.Tab + e.Row.ItemArray ( 0 ).ToString ( ) )
End Sub

Private Sub PrintValues ( ds As DataSet, label As String )
   Response.Write ( ControlChars.Cr + label )
   Dim tbl As DataTable
   Dim row As DataRow
   Dim col As DataColumn
   For Each tbl In  ds.Tables
      Response.Write ( "TableName: " + tbl.TableName )
      For Each row In  tbl.Rows
         For Each col In  tbl.Columns
            Response.Write ( ControlChars.Tab + " " + Row ( col ).ToString ( ) )
         Next col
         Response.Write ( )
      Next row
   Next tbl
End Sub