private void menuAdmin_Click(object sender, EventArgs e)
        {
            if (listForm.Count != 0)
            {
                listForm[listForm.Count - 1].Close();
                listForm.RemoveAt(listForm.Count - 1);
            }
            fAdmin f = new fAdmin();

            f.MdiParent = this;
            f.Show();
        }
        private void nemuAdmin_Click(object sender, EventArgs e)
        {
            fAdmin f = new fAdmin();

            f.ShowDialog();
        }