private void Btn_Login_Click(object sender, EventArgs e)
        {
            using (HotelEntities hotelEntities = new HotelEntities())
            {
                var query = from login in hotelEntities.Login
                            where login.Username.Equals(T_Username.Text.Trim()) && login.Password.Equals(T_Password.Text.Trim())
                            select login;

                if (query.ToList().Count > 0)
                {
                    this.Hide();
                    ShapedForm1 frm = new ShapedForm1();
                    frm.Show();
                }
                else
                {
                    htmlToolTip1.Show("Verifier le nom d'utilisateur !", T_Username, 2500);
                    htmlToolTip2.Show("Verifier le Password !", T_Password, 2500);
                    MessageBox.Show("Verifier le nom d'utilisateur et/ou le mot de passe !");
                }
            }
        }
        private void T_Password_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == 13)
            {
                using (HotelEntities hotelEntities = new HotelEntities())
                {
                    var query = from login in hotelEntities.Login
                                where login.Username.Equals(T_Username.Text.Trim()) && login.Password.Equals(T_Password.Text.Trim())
                                select login;

                    if (query.ToList().Count > 0)
                    {
                        this.Hide();
                        ShapedForm1 frm = new ShapedForm1();
                        frm.Show();
                    }
                    else
                    {
                        htmlToolTip1.Show("Verifier le nom d'utilisateur !", T_Username, 2500);
                        htmlToolTip2.Show("Verifier le Password !", T_Password, 2500);
                    }
                }
            }
        }