1.本地无缓存，每次自动刷新
response.expires=0
response.addheader"pragma","no-cache"
response.addheader"cache-control","private"

2.修改contenttype并下载gif等格式
<%
functiondl(f,n)
onerrorresumenext

sets=createobject("adodb.stream")
s.mode=3
s.type=1
s.open
s.loadfromfile(server.mappath(f))
iferr.number>0then
response.writeerr.number&":"&err.description
else
response.contenttype="application/x-gzip"
response.addheader"content-disposition:","attachment;filename="&n
response.binarywrite(s.read(s.size))
endif
endfunction

calldl("012922501.gif","t1.gif")
%>

19.检查一段字符串是否全由数字组成
<scriptlanguage="javascript"><!--
functionchecknum(str){return!/\d/.test(str)}
alert(checknum("1232142141"))
alert(checknum("123214214a1"))
//--></script>

20.获得一个窗口的大小
document.body.clientwidth,document.body.clientheight
document.body.offsetwidth,document.body.offsetheight
有时还需要知道window.screentop,window.screenleft

21.怎么判断是否含有汉字
if(escape(str).indexof("%u")!=-1)alert("含有汉字");
elsealert("全是字符");

22.textarea自适应文字行数的多少
ie5.5+可以用overflow-y:visible
<textarearows=1name=s1cols=27style="overflow-y:visible">
</textarea>

23.日期减去天数等于第二个日期
<scriptlanguage=javascript>
functioncc(dd,dadd)
{
//可以加上错误处理
vard=newdate(dd.replace("-","/"))
d.setdate(d.getdate()+dadd)
alert(d.getfullyear()+"年"+(d.getmonth()+1)+"月"+d.getdate()+"日")
}
cc("2002-2-28",2)
</script>