DateTime dt = DateTime.Now;
DateTime startWeek = dt.AddDays(1 - Convert.ToInt32(dt.DayOfWeek.ToString(
"d"
)));
DateTime endWeek = startWeek.AddDays(6);
DateTime startMonth = dt.AddDays(1 - dt.Day);
DateTime endMonth = startMonth.AddMonths(1).AddDays(-1);
DateTime startQuarter = dt.AddMonths(0 - (dt.Month - 1) % 3).AddDays(1 - dt.Day);
DateTime endQuarter = startQuarter.AddMonths(3).AddDays(-1);
DateTime startYear =
new
DateTime(dt.Year, 1, 1);
DateTime endYear =
new
DateTime(dt.Year, 12, 31);
至于昨天、明天、上周、上月、上季度、上年度等等,只要AddDays()、AddMonths()、AddYears()这几种方法组合一下就可以了。
C#中datetime的使用
string
[] Day =
new
string
[] {
"星期日"
,
"星期一"
,
"星期二"
,
"星期三"
,
"星期四"
,
"星期五"
,
"星期六"
};
string
week = Day[Convert.ToInt32(DateTime.Now.DayOfWeek.ToString(
"d"
))].ToString();
DateTime.Now.AddDays(Convert.ToInt32 (1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) - 7);
DateTime.Now.AddDays(Convert.ToInt32 (1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) - 7).AddDays(6);
DateTime.Now.AddDays(Convert.ToInt32 (1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) + 7);
DateTime.Now.AddDays(Convert.ToInt32(1 - Convert.ToInt32(DateTime.Now.DayOfWeek)) + 7).AddDays(6);
DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() +
"1"
;
DateTime.Parse(DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() +
"1"
).AddMonths(1).AddDays(-1).ToShortDateString();
1).ToShortDateString();
DateTime.Now.ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(1).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(2).AddDays(-1).ToShortDateString();
DateTime.Now.Date.ToShortDateString();
DateTime.Now.AddDays(7).ToShortDateString();
DateTime.Now.AddDays(-7).ToShortDateString();
DateTime.Now.Date.ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(1).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(2).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).AddDays(1 - DateTime.Now.Day);
DateTime.Parse(DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.AddMonths(6 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(-3 - ((DateTime.Now.Month - 1) % 3)). AddDays(1 - DateTime.Now);
DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).AddDays(1 - DateTime.Now.Day).AddDays(-1).ToShortDateString();
DateTime.Now.Date.ToShortDateString();
DateTime.Now.AddDays(-1).ToShortDateString();
DateTime.Now.AddDays(1).ToShortDateString();
DateTime.Now.AddDays(Convert.ToDouble((0 - Convert.ToInt16(DateTime.Now.DayOfWeek)))).ToShortDateString();
DateTime.Now.AddDays(Convert.ToDouble((6 - Convert.ToInt16(DateTime.Now.DayOfWeek)))).ToShortDateString();
string
[] Day =
new
string
[] {
"星期日"
,
"星期一"
,
"星期二"
,
"星期三"
,
"星期四"
,
"星期五"
,
"星期六"
};
Day[Convert.ToInt16(DateTime.Now.DayOfWeek)];
DateTime.Now.AddDays(Convert.ToDouble((0 - Convert.ToInt16(DateTime.Now.DayOfWeek))) - 7).ToShortDateString();
DateTime.Now.AddDays(Convert.ToDouble((6 - Convert.ToInt16(DateTime.Now.DayOfWeek))) - 7).ToShortDateString();
DateTime.Now.AddDays(Convert.ToDouble((0 - Convert.ToInt16(DateTime.Now.DayOfWeek))) + 7).ToShortDateString();
DateTime.Now.AddDays(Convert.ToDouble((6 - Convert.ToInt16(DateTime.Now.DayOfWeek))) + 7).ToShortDateString();
DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() +
"1"
;
DateTime.Parse(DateTime.Now.Year.ToString() + DateTime.Now.Month.ToString() +
"1"
).AddMonths(1).AddDays(-1).ToShortDateString();
DateTime.Now.ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(1).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-MM-01"
)).AddMonths(2).AddDays(-1).ToShortDateString();
DateTime.Now.Date.ToShortDateString();
DateTime.Now.AddDays(7).ToShortDateString();
DateTime.Now.AddDays(-7).ToShortDateString();
DateTime.Now.Date.ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(1).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddDays(-1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(1).ToShortDateString();
DateTime.Parse(DateTime.Now.ToString(
"yyyy-01-01"
)).AddYears(2).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(3 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.AddMonths(6 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();
DateTime.Now.AddMonths(-3 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
);
DateTime.Parse(DateTime.Now.AddMonths(0 - ((DateTime.Now.Month - 1) % 3)).ToString(
"yyyy-MM-01"
)).AddDays(-1).ToShortDateString();