‍--查询当天：     select * from info where DateDiff(dd,datetime,getdate())=0         --查询24小时内的:     select * from info where DateDiff(hh,datetime,getDate())     --info为表名,datetime为数据库中的字段值    --查询当

获取当前日期周数  C#：int str = new System.Globalization.GregorianCalendar().GetWeekOfYear(System.DateTime.Now, System.Globalization.CalendarWeekRule.FirstDay, DayOfWeek.Sunday); SQL：select datepart(week,'20