private void setBsnav()
{
  bs = new BindingSource();
  bs.DataSource = ds.Tables[0];
  bsnav.BindingSource = bs;
}

private void bindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
  da.Update(ds.Tables[0]);
}

private void bindingNavigatorDeleteItem_Click(object sender, EventArgs e)
{
  da.Update(ds.Tables[0]);
}

private void bindingNavigatorMoveNextItem_Click(object sender, EventArgs e)
{
  bs.MoveNext();
}

private void bindingNavigatorMovePreviousItem_Click(object sender, EventArgs e)
{
  bs.MovePrevious();

}

private void bindingNavigatorMoveFirstItem_Click(object sender, EventArgs e)
{
  bs.MoveFirst();
}

private void bindingNavigatorMoveLastItem_Click(object sender, EventArgs e)
{
  bs.MoveLast();
}