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