从一个插件搞来的
<%@LANGUAGE="VBSCRIPT" CODEPAGE="936"%>




<% Const DAILY_DIR = "/imags/"
Dim objDSO, objDailyFolderObject, objDailyCollection, objDaily
Dim intDailyNumberToUse, intDailyLooper
Dim objDailyImageToUse
Dim strDailySrcText
Set objDSO = Server.CreateObject("Scripting.FileSystemObject")
Set objDailyFolderObject = objDSO.GetFolder(Server.MapPath(DAILY_DIR))
Set objDSO = Nothing
Set objDailyCollection = objDailyFolderObject.Files
Set objDailyFolderObject = Nothing
Dim myDate
myDate = cDate("September 27, 1969")
intDailyNumberToUse = DateDiff("d", myDate, Date) MOD objDailyCollection.Count
intDailyLooper = 1
For Each objDaily in objDailyCollection
    If intDailyLooper = intDailyNumberToUse Then
        Set objDailyImageToUse = objDaily
        Exit For
    End If
    intDailyLooper = intDailyLooper + 1
Next
Set objDailyCollection = Nothing
strDailySrcText = DAILY_DIR & objDailyImageToUse.Name
Set objDailyImageToUse = Nothing
%>