上个月第一天：<%=dateadd("m",-1,year(date)&"-"&month(date)&"-1")%>
上个月最后一天：<%=dateadd("d",-1,year(date)&"-"&month(date)&"-1")%>
本月第一天：<%=year(date)&"-"&month(date)&"-1"%>
本月最后一天：<%=dateadd("d",-1,dateadd("m",1,year(date)&"-"&month(date)&"-1"))%>
下个月第一天：<%=dateadd("m",1,year(date)&"-"&month(date)&"-01")%>
下个月最后一天：<%=dateadd("d",-1,dateadd("m",2,year(date)&"-"&month(date)&"-01"))%>
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data=dateadd("d",0,year(date)&"-"&month(date)&"-"&day(date))
zdata=(date()-1)

toy=Weekday(data,2) 
zhou1=dateadd("d",date(),(-(toy-1)))
zhour=dateadd("d",zhou1,6)

yue1=dateadd("d",0,year(date)&"-"&month(date)&"-1")
yue2=dateadd("d",-1,dateadd("m",1,yue1))

syue1=dateadd("m",-1,yue1)
syue2=dateadd("d",-1,yue1)

response.Write("今天："&data&"<br>周："&zhou1&"-"&zhour&"<br>本月："&yue1&"-"&yue2&"<br>上月："&syue1&"-"&syue2)