private void btnEditFlat_Click(object sender, EventArgs e)
{
curIDFlat = (int)dgvFlat.Rows[dgvFlat.CurrentRow.Index].Cells[0].Value;
Flat Flat = new Flat(curIDFlat);
Flat.Show();
}
private void btnAddFlat_Click(object sender, EventArgs e)
{
Flat Flat = new Flat();
Flat.Show();
}