private void lbl_cusR_Click(object sender, EventArgs e)
        {
            pnl_rpots.Controls.Clear();
            Rpot_CustomerList rcusl = new Rpot_CustomerList();

            rcusl.TopLevel = false;
            rcusl.Visible  = true;
            pnl_rpots.Controls.Add(rcusl);
        }
        private void customerListToolStripMenuItem_Click(object sender, EventArgs e)
        {
            panelMain.Controls.Clear();
            Report_main View_rpt = new Report_main();

            View_rpt.TopLevel = false;
            View_rpt.Visible  = true;
            panelMain.Controls.Add(View_rpt);

            Report_main.pn_Rpot.Controls.Clear();
            Rpot_CustomerList rcusl = new Rpot_CustomerList();

            rcusl.TopLevel = false;
            rcusl.Visible  = true;
            Report_main.pn_Rpot.Controls.Add(rcusl);
        }