private void InitializeConstructor()
        {
            ComboFunctions.FillEscortCombo(ddlEscort, null);
            ComboFunctions.FillBookingTypeCombo(ddlBookingType);
            ddlBookingType.SelectedValue = Enums.BOOKING_TYPES.LOCAL;

            dtpInvoiceDate.Value = DateTime.Now.ToDate();
            dtpDueDate.Value     = DateTime.Now.ToDate().AddMonths(1);
            FormatChargesGrid();

            grdLister.ShowGroupPanel      = false;
            grdLister.AutoCellFormatting  = true;
            grdLister.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
            grdLister.ShowRowHeaderColumn = false;

            objMaster = new InvoiceBO();
            this.SetProperties((INavigation)objMaster);

            grdLister.AllowAddNewRow = false;


            dtpFromDate.Value = new DateTime(DateTime.Now.Year, DateTime.Now.Month, 1);
            dtpTillDate.Value = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.LastDayOfMonthValue());



            grdLister.CommandCellClick += new CommandCellClickEventHandler(grdLister_CommandCellClick);
        }