Path=request.querystring("p")
sPath = Path
if left(lcase(path),7) <> "http://" then
'-------------如果前面没有http就是本地文件，交给LocalFile处理------------
LocalFile(path)
else
'--------------------否则为远程文件，交给RemoteFile处理------------------
RemoteFile(Path)
end if
'Response.Write err.Description

sub LocalFile(Path)
'-------------------如果为本地文件则简单的跳转到该页面-------------------
Response.Redirect Path
End Sub

Sub RemoteFile(sPath)
'-------------------------处理远程文件函数------------------------------
FileName = GetFileName(sPath)
'-------------GetFileName为把地址转换为合格的文件名过程-------------
FileName = Server.MapPath("/UploadFile/Cache/" & FileName)
Set objFso = Server.CreateObject("Scripting.FileSystemObject")
'Response.Write fileName
if objFso.FileExists(FileName) Then
'--------------检查文件是否是已经访问过,如是，则简单跳转------------
Response.Redirect "/uploadfile/cache/" & GetFileName(path)
Else
'----------------否则的话就先用GetBody函数读取----------------------
'Response.Write Path
t = GetBody(Path)
'-----------------用二进制方法写到浏览器上--------------------------
Response.BinaryWrite t
Response.Flush
'-----------------输出缓冲------------------------------------------
SaveFile t,GetFileName(path)
'------------------将文件内容缓存到本地路径，以待下次访问-----------
End if
Set objFso = Nothing
End Sub

Function GetBody(url)
'-----------------------本函数为远程获取内容的函数---------------------
'on error resume next
'Response.Write url
Set Retrieval = CreateObject("Microsoft.XMLHTTP")
'----------------------建立XMLHTTP对象-----------------------------
With Retrieval
.Open "Get", url, False, "", ""
'------------------用Get，异步的方法发送-----------------------
.Send
'GetBody = .ResponseText
GetBody = .ResponseBody
'------------------函数返回获取的内容--------------------------
End With
Set Retrieval = Nothing
'response.Write err.Description
End Function

Function GetFileName(str)
'-------------------------本函数为合格化的文件名函数-------------------
str = Replace(lcase(str),"http://","")
str = Replace(lcase(str),"//","/")
str = Replace(str,"/","")
str = replace(str,vbcrlf,"")
GetFileName = str
End Function

sub SaveFile(str,fName)
'-------------------------本函数为将流内容存盘的函数-------------------
'on error resume next
Set objStream = Server.CreateObject("ADODB.Stream")
'--------------建立ADODB.Stream对象，必须要ADO 2.5以上版本---------
objStream.Type = adTypeBinary
'-------------以二进制模式打开-------------------------------------
objStream.Open
objstream.write str
'--------------------将字符串内容写入缓冲--------------------------
'response.Write fname
objstream.SaveToFile "c:\inetpub\myweb\uploadfile\cache\" & fName,adSaveCreateOverWrite
'--------------------将缓冲的内容写入文件--------------------------
'response.BinaryWrite objstream.Read
objstream.Close()
set objstream = nothing
'-----------------------关闭对象，释放资源-------------------------
'response.Write err.Description
End sub
%>

（出处：开发者俱乐部）