/// 
        /// 选择日期        /// 
        private void RQTxt_MouseWheel(object sender, MouseWheelEventArgs e)        {            if (XZQTxt.IsSelectionActive && XZQTxt.Text != null)                Math(e.Delta, XZQTxt);        }        /// 
        /// 输入月份更新文本        /// 
        /// 滚轮上翻（正）还是下翻（负）        /// 事件发生前的文本值        public void Math(int e, TextBox time)        {            string text = time.Text;            ShowTXT(time, e, text, text.Substring(4, 2), "31", "30");            switch (text.Substring(4, 2))            {                case "05":                    ShowTXT(time, e, text, "05", "31", "30");                    break;                case "06":                    ShowTXT(time, e, text, "06", "30", "31");                    break;                case "07":                    ShowTXT(time, e, text, "07", "31", "30");                    break;                case "08":                    ShowTXT(time, e, text, "08", "31", "31");                    break;                case "09":                    ShowTXT(time, e, text, "09", "30", "31");                    break;                default:                    break;            }        }        /// 
        /// 显示文本        /// 
        /// 滚轮上翻（正）还是下翻（负）        /// 事件发生前的文本值        /// 月份        /// 这月的天数        /// 上月的天数        public void ShowTXT(TextBox time, int e, string text, string YF, string ZYS, string SYS)        {            if (Convert.ToInt32(text.Substring(6, 2)) + (e / 120) > Convert.ToInt32(ZYS) && e > 0)                time.Text = text.Substring(0, 4) + "0" + (Convert.ToInt32(YF.Substring(1)) + 1) + "01";            else if ((Convert.ToInt32(text) + (e / 120)).ToString().Substring(6, 2) == "00" && e < 0)                time.Text = text.Substring(0, 4) + "0" + (Convert.ToInt32(YF.Substring(1)) - 1) + SYS;            else                time.Text = (Convert.ToInt32(text) + e / 120).ToString();        }