public void LHD()
 {
     //  this.fluentDesignFormContainer1.Controls.Clear();
     LapHoaDon tk = new LapHoaDon();
     //  tk.TopLevel = false;
     //  tk.Dock = DockStyle.Fill;
     // this.fluentDesignFormContainer1.Controls.Add(tk);
     tk.ShowDialog();
 }
        private void barButtonItem1_ItemClick(object sender, ItemClickEventArgs e)
        {
            //TrangChu tc = new TrangChu();
            //tc.fluentDesignFormContainer1.Controls.Clear();
            LapHoaDon tb = new LapHoaDon();

            tb.TopLevel = false;
            this.tableLayoutPanel1.Controls.Add(tb);
            tb.Show();

            //this.tableLayoutPanel1.Controls.Clear();
            //LapHoaDon tb = new LapHoaDon();
            //tb.TopLevel = false;
            //this.tableLayoutPanel1.Controls.Add(tb);
            //tb.Show();
        }