private void BtnLogin_Click(object sender, EventArgs e)
        {
            MainRibbonForm MainRibbon = new MainRibbonForm();
            string         Login      = TxtLogin.Text.Trim();
            string         Motdepass  = TwtPwd.Text.Trim();

            if (string.IsNullOrEmpty(Login))
            {
                TxtLogin.ErrorText = "Login  est obligatoire";
                return;
            }
            if (string.IsNullOrEmpty(Motdepass))
            {
                TwtPwd.ErrorText = "Password  est obligatoire";
                return;
            }



            var Utilisateur = ProcessLogin(Login, Motdepass);

            if (Utilisateur != null)
            {
                MainRibbon.Show();
                this.Hide();
                Formshow(Forms.FrmAcceuil.InstanceFrmAcceuil, MainRibbon);
            }
        }
 public void Formshow(Form frm, MainRibbonForm frm1)
 {
     // waiting Form
     SplashScreenManager.ShowForm(this, typeof(Forms.FrmWaitForm), true, true, false);
     SplashScreenManager.Default.SetWaitFormCaption("Processesing in Data ....");
     for (int i = 0; i < 100; i++)
     {
         Thread.Sleep(10);
     }
     SplashScreenManager.CloseForm();
     //waiting Form
     frm.MdiParent = frm1;
     frm.Show();
     frm.Activate();
 }