Private Sub DataTableRowChanging()
     Dim custTable As DataTable = New DataTable("Customers")
     ' add columns
     custTable.Columns.Add("id", Type.GetType("System.Int32"))
     custTable.Columns.Add("name", Type.GetType("System.String"))
     custTable.Columns.Add("address", Type.GetType("System.String"))

     ' set PrimaryKey
     custTable.Columns("id").Unique = True
     custTable.PrimaryKey = New DataColumn() {custTable.Columns("id")}

     ' add a RowChanging event handler for the table.
     AddHandler custTable.RowChanging, _
            New DataRowChangeEventHandler(AddressOf Row_Changing)


     ' add ten rows
     Dim id As Integer
     For id = 1 To 10
         custTable.Rows.Add( _
New Object() {id, String.Format("customer{0}", id), _
         String.Format("address{0}", id)})
     Next

     custTable.AcceptChanges()

     ' change the name column in all the rows
     Dim row As DataRow
     For Each row In custTable.Rows
         row("name") = String.Format("vip{0}", row("id"))
     Next

 End Sub

 Private Sub Row_Changing(ByVal sender As Object, _
 ByVal e As DataRowChangeEventArgs)
     Console.WriteLine("Row_Changing Event: name={0}; action={1}", _
      e.Row("name"), e.Action)
 End Sub

private static void DataTableRowChanging()
{
	DataTable custTable = new DataTable("Customers");
	// add columns
	custTable.Columns.Add("id", typeof(int));
	custTable.Columns.Add("name", typeof(string));
	custTable.Columns.Add("address", typeof(string));

	// set PrimaryKey
	custTable.Columns[ "id" ].Unique = true;
	custTable.PrimaryKey = new DataColumn[] { custTable.Columns["id"] };

	// add a RowChanging event handler for the table.
	custTable.RowChanging += new DataRowChangeEventHandler(Row_Changing);


	// add ten rows
	for(int id=1; id<=10; id++)
	{
		custTable.Rows.Add(
			new object[] { id, string.Format("customer{0}", id), 
            string.Format("address{0}", id) });
	}
	
	custTable.AcceptChanges();

	// change the name column in all the rows
	foreach(DataRow row in custTable.Rows)
	{
		row["name"] = string.Format("vip{0}", row["id"]);
	}

}

private static void Row_Changing(object sender, DataRowChangeEventArgs e)
{
	Console.WriteLine("Row_Changing Event: name={0}; action={1}", 
		e.Row["name"], e.Action);
}