private void button3_Click(object sender, EventArgs e)
{
List <int> marked = Methods.getIdFromColumnNO(1, dataGridView1.SelectedRows);
var form = new FormFlats();
form.dataGridView1.DataSource = form.Dataset.Where(x => marked.Contains(x.identyfikator_mieszkania)).ToList();
form.Show();
}
private void button13_Click(object sender, EventArgs e)
{
var form = new FormFlats();
form.Show();
}