日期对象处理

thisMonth()    //返回月初

thisMonthEnd()    //返回月末

thisSeason()    //返回季度初

thisSeasonEnd()    //返回季度末

thisYear()    //返回年初

thisYearEnd()    //返回年末

public String thisMonth(DateTime date)
        {
            String strY = null;
            int x, y;
            x = Convert.ToInt32(date.Year.ToString());
            y = Convert.ToInt32(date.Month.ToString());
            strY = y >= 10 ? y.ToString() : ("0" + y); return x + "年" + strY + "月01日";
        }

        public String thisMonthEnd(DateTime date)
        {
            int x, y;
            String strY = null;
            String strZ = null;
            bool leap = false;
            x = Convert.ToInt32(date.Year.ToString());
            y = Convert.ToInt32(date.Month.ToString());
            if (y == 1 || y == 3 || y == 5 || y == 7 || y == 8 || y == 10 || y == 12)
            {
                strZ = "31";
            }
            if (y == 4 || y == 6 || y == 9 || y == 11)
            {
                strZ = "30";
            }
            if (y == 2)
            {
                leap = leapYear(x);
                if (leap)
                {
                    strZ = "29";
                }
                else
                {
                    strZ = "28";
                }
            }
            strY = y >= 10 ? y.ToString() : ("0" + y);
            return x + "年" + strY + "月" + strZ + "日";
        }

        public String thisSeason(DateTime date)
        {
            String dateString = "";
            int x, y;
            x = Convert.ToInt32(date.Year.ToString());
            y = Convert.ToInt32(date.Month.ToString());
            if (y >= 1 && y <= 3)
            {
                dateString = x + "-" + "01" + "-" + "01";
            }
            if (y >= 4 && y <= 6)
            {
                dateString = x + "-" + "04" + "-" + "01";
            }
            if (y >= 7 && y <= 9)
            {
                dateString = x + "-" + "07" + "-" + "01";
            }
            if (y >= 10 && y <= 12)
            {
                dateString = x + "-" + "10" + "-" + "01";
            }
            return dateString;
        }

        public String thisSeasonEnd(DateTime date)
        {
            String dateString = "";
            int x, y;
            x = Convert.ToInt32(date.Year.ToString());
            y = Convert.ToInt32(date.Month.ToString());
            if (y >= 1 && y <= 3)
            {
                dateString = x + "-" + "03" + "-" + "31";
            }
            if (y >= 4 && y <= 6)
            {
                dateString = x + "-" + "06" + "-" + "30";
            }
            if (y >= 7 && y <= 9)
            {
                dateString = x + "-" + "09" + "-" + "30";
            }
            if (y >= 10 && y <= 12)
            {
                dateString = x + "-" + "12" + "-" + "31";
            }
            return dateString;
        }

        public String thisYear(DateTime date)
        {
            int x;
            x = Convert.ToInt32(date.Year.ToString());
            return x + "-01" + "-01";
        }

        public String thisYearEnd(DateTime date)
        {
            int x;
            x = Convert.ToInt32(date.Year.ToString());
            return x + "-12" + "-31";
        }

        public bool leapYear(int year)
        {
            bool leap;
            if (year % 4 == 0)
            {
                if (year % 100 == 0)
                {
                    if (year % 400 == 0) leap = true;
                    else leap = false;
                }
                else leap = true;
            }
            else leap = false;
            return leap;
        }