C#获取周一、周日的日期 函数类

 

#region 得到一周的周一和周日的日期
        /// <summary>
        /// 计算本周的周一日期
        /// </summary>
        /// <returns></returns>
        public static DateTime GetMondayDate()
        {
            return GetMondayDate(DateTime.Now);
        }
        /// <summary>
        /// 计算本周周日的日期
        /// </summary>
        /// <returns></returns>
        public static DateTime GetSundayDate()
        {
            return GetSundayDate(DateTime.Now);
        }
        /// <summary>
        /// 计算某日起始日期(礼拜一的日期)
        /// </summary>
        /// <param name="someDate">该周中任意一天</param>
        /// <returns>返回礼拜一日期,后面的具体时、分、秒和传入值相等</returns>
        public static DateTime GetMondayDate(DateTime someDate)
        {
            int i = someDate.DayOfWeek - DayOfWeek.Monday;
            if (i == -1) i = 6;// i值 > = 0 ,因为枚举原因,Sunday排在最前,此时Sunday-Monday=-1,必须+7=6。
            TimeSpan ts = new TimeSpan(i, 0, 0, 0);
            return someDate.Subtract(ts);
        }
        /// <summary>
        /// 计算某日结束日期(礼拜日的日期)
        /// </summary>
        /// <param name="someDate">该周中任意一天</param>
        /// <returns>返回礼拜日日期,后面的具体时、分、秒和传入值相等</returns>
        public static DateTime GetSundayDate(DateTime someDate)
        {
            int i = someDate.DayOfWeek - DayOfWeek.Sunday;
            if (i != 0) i = 7 - i;// 因为枚举原因,Sunday排在最前,相减间隔要被7减。
            TimeSpan ts = new TimeSpan(i, 0, 0, 0);
            return someDate.Add(ts);
        }
        #endregion

 

////////////////////////////////////////收集其它的方法/////////////////////////////////////

DateTime dt = DateTime.Now;  //当前时间

DateTime startWeek = dt.AddDays(1 - Convert.ToInt32(dt.DayOfWeek.ToString("d")));  //本周周一
DateTime endWeek = startWeek.AddDays(6);  //本周周日

 DateTime startMonth = dt.AddDays(1 - dt.Day);  //本月月初
DateTime endMonth = startMonth.AddMonths(1).AddDays(-1);  //本月月末
//DateTime endMonth = startMonth.AddDays((dt.AddMonths(1) - dt).Days - 1);  //本月月末

DateTime startQuarter = dt.AddMonths(0 - (dt.Month - 1) % 3).AddDays(1 - dt.Day);  //本季度初
DateTime endQuarter = startQuarter.AddMonths(3).AddDays(-1);  //本季度末

DateTime startYear = new DateTime(dt.Year, 1, 1);  //本年年初
DateTime endYear = new DateTime(dt.Year, 12, 31);  //本年年末

本文来自CSDN博客,转载请标明出处:http://blog.csdn.net/guoyz_1/archive/2009/01/15/3785705.aspx

posted @ 2011-01-24 17:26  小马的酒吧  阅读(8568)  评论(1编辑  收藏  举报