[MSSQL]根据周数返回日期

/* FUNCTION:根据周数返回日期 Author:Stickman Date:2005.08.10 Version:1.0 返回:日子字符串输入1:年输入2:周数 */

 CREATE function Week2Day(@intYear integer,@intWeek integer)

returns varchar(50)

as

begin

declare @dateFirstDayOfYear datetime declare @dateFirstDayOfWeek datetime declare @dateLastDayOfWeek datetime

set @dateFirstDayOfYear=convert(smalldatetime,convert(varchar(4),@intYear) + '-1-1')

set @dateFirstDayOfWeek=dateadd(day,1-datePart(weekday,@dateFirstDayOfYear),dateAdd(week,@intWeek-1,@dateFirstDayOfYear))

 set @dateLastDayOfWeek=dateadd(day,6,@dateFirstDayOfWeek)

RETURN convert(varchar(10),@dateFirstDayOfWeek,11) + '～' + convert(varchar(10),@dateLastDayOfWeek,11) end