知道周求时间范围

 
SET DATEFIRST 1

declare @strTime nvarchar(50);
set @strTime='week8'; --8月

declare @CurYear int;
select @CurYear=datepart(year,GETDATE());
declare @dateFirstDayOfYear datetime; --年的第一天
declare @dateFirstDayOfWeek datetime;--周的第一天
declare  @dateLastDayOfWeek datetime;--周的最后一天
declare @whichtime nvarchar(50); --月或周的数量
declare @startTime datetime; --月的第一天
declare @EndTime datetime; --月的最后一天
declare @Monthlocation int; --月字段的位置
declare @WeekLocation int; --周字段的位置
set @Monthlocation=charindex('月',@strTime);
set @WeekLocation=charindex('week',@strTime);
--求月时间范围
if(@Monthlocation>0)
begin
 set @whichtime=replace(@strTime,'月','');
 set @startTime=cast((cast(@CurYear as varchar(4))+'-'+@whichtime+'-1') as datetime);
 set @EndTime=dateadd(day,-1,dateadd(month,1,@startTime));
 
 select @startTime,@EndTime;
end

--求周时间范围
if(@WeekLocation>0)
begin
 set @whichtime=replace(@strTime,'week','');
 set @dateFirstDayOfYear=cast((cast(@CurYear as varchar(4))+'-1-1') as datetime);
 set @dateFirstDayOfWeek=dateadd(day,1-datePart(weekday,@dateFirstDayOfYear),dateAdd(week,@whichtime-1,@dateFirstDayOfYear));
 set @dateLastDayOfWeek=dateadd(day,6,@dateFirstDayOfWeek);
    select @dateFirstDayOfWeek,@dateLastDayOfWeek;
end