private void addButton_Click(object sender, EventArgs e)
{
ForeignKey key = new ForeignKey(tableNode.Table, null);
if (refTable.SelectedValue != null)
{
key.SetName(String.Format("FK_{0}_{1}", tableNode.Table.Name,
refTable.SelectedValue), true);
key.ReferencedTable = refTable.SelectedValue.ToString();
}
foreignKeyBindingSource.Add(key);
}