private void button1_Click(object sender, EventArgs e)
        {
            DialogResult dr = MessageBox.Show(TxtName.Text + " Personelini Kaydetmek İstiyor Musunuz ?", "Soru", MessageBoxButtons.YesNo, MessageBoxIcon.Question);

            if (dr == DialogResult.Yes)
            {
                Personnel personnel = new Personnel(CmbDepartment.SelectedValue.ConInt(), CmbAuth.SelectedValue.ConInt(), MskSicilNo.Text, TxtName.Text);
                MessageBox.Show(personnelManager.Add(personnel));

                var form = (FrmPersonnels)Application.OpenForms["FrmPersonnels"];
                form.PersonnelList();
            }
        }