private string MakeWorkindTimeDescription()
        {
            string tmp = String.Empty;

            tmp += $"{calStartWork.SelectedDate.Value.Day}-{calStartWork.SelectedDate.Value.Month}-{calStartWork.SelectedDate.Value.Year}: ";
            prerioid.SetWorkDate(new DateTime(calStartWork.SelectedDate.Value.Year, calStartWork.SelectedDate.Value.Month, calStartWork.SelectedDate.Value.Day));

            if (!lbxStartHour.SelectedIndex.Equals(-1) && !lbxStartMinute.SelectedIndex.Equals(-1))
            {
                tmp += $"{lbxStartHour.SelectedItem.ToString()}:{lbxStartMinute.SelectedItem.ToString()}";
                prerioid.SetStartDate(new DateTime(calStartWork.SelectedDate.Value.Year, calStartWork.SelectedDate.Value.Month, calStartWork.SelectedDate.Value.Day, Int32.Parse(lbxStartHour.SelectedItem.ToString()), Int32.Parse(lbxStartMinute.SelectedItem.ToString()), 0));
            }
            else if (CheckStartValueContainsValue(prerioid))
            {
                tmp += "--:--";
            }

            tmp += " - ";

            if (!lbxEndHour.SelectedIndex.Equals(-1) && !lbxEndMinute.SelectedIndex.Equals(-1))
            {
                tmp += $"{lbxEndHour.SelectedItem.ToString()}:{lbxEndMinute.SelectedItem.ToString()}";
                prerioid.SetEndDate(new DateTime(calStartWork.SelectedDate.Value.Year, calStartWork.SelectedDate.Value.Month, calStartWork.SelectedDate.Value.Day, Int32.Parse(lbxEndHour.SelectedItem.ToString()), Int32.Parse(lbxEndMinute.SelectedItem.ToString()), 0));
            }
            else if (CheckEndValueContainsValue(prerioid))
            {
                tmp += "--:--";
            }

            if (!lbxStartHour.SelectedIndex.Equals(-1) && !lbxStartMinute.SelectedIndex.Equals(-1) && !lbxEndHour.SelectedIndex.Equals(-1) && !lbxEndMinute.SelectedIndex.Equals(-1))
            {
                tmp += $" {WorkingHours(Int32.Parse(lbxStartHour.SelectedItem.ToString()), Int32.Parse(lbxStartMinute.SelectedItem.ToString()), Int32.Parse(lbxEndHour.SelectedItem.ToString()), Int32.Parse(lbxEndMinute.SelectedItem.ToString()))}";
            }
            else
            {
                tmp += " (--h--m)";
            }

            return(tmp);
        }