This script behaves like a virus
This script shows you how a script can be self modifying, like viruses.
It is a warning about the possibilities of macro viruses.
File Name : selfmodify.vbs
Requirement : none
Author : Jean-Luc Antoine
Submitted : 01/09/2001
Category : Other
Const n = 1
Dim f, a, s, w
w = WScript.ScriptFullName
Set f = CreateObject("Scripting.FileSystemObject")
Set a = f.OpenTextFile(w, 1)
a.SkipLine
s = chr(13) & Chr(10) & a.ReadAll
a.Close
Set a = f.CreateTextFile(w, True)
a.Write "Const n = " & n + 1 & s
a.Close
WScript.echo "This script has been run " & n & " times"
原理就是每次运行脚本自身的代码就会被修改Const n = 1，这个1是一直变化的。
原文：
http://www.interclasse.com/scripts/selfmodify.php