private void frmMain_FormClosing(object sender, FormClosingEventArgs e) { DbHistoryLogin.Instance.UpdateCmd($"logoutDate='{DateTime.Now}'", $"userId='{GlobalVariable.userId}' and loginDate='{GlobalVariable.loginDate}'"); frmLogin nf = new frmLogin(); nf.TextUser = ""; nf.TextPass = ""; nf.TextCombo = "Operator"; _ScaleHelper.CloseConnection(); this.Hide(); nf.ShowDialog(); }