北京农村商业银行地址:求一个ASP的验证码程序

<%@LANGUAGE="VBSCRIPT" CODEPAGE="936"%>
<!--#include file="commonfile/md5.asp"-->
<%
'-----------------------------------------------------生成验证码图像
Function NumCode()
Response.Expires = -1
Response.AddHeader "Pragma","no-cache"
Response.AddHeader "cache-ctrol","no-cache"
dim zNum,i,j
dim Ados,Ados1
Randomize timer
zNum = cint(8999*Rnd+1000)
Session("chk") = md5(zNum)
dim zimg(4),NStr
NStr=cstr(zNum)
For i=0 to 3
zimg(i)=cint(mid(NStr,i+1,1))
Next
dim Pos
set Ados=Server.CreateObject("Adodb.Stream")
Ados.Mode=3
Ados.Type=1
Ados.Open
set Ados1=Server.CreateObject("Adodb.Stream")
Ados1.Mode=3
Ados1.Type=1
Ados1.Open
Ados.LoadFromFile(Server.mappath("img_body.asp"))
Ados1.write Ados.read(1280)
for i=0 to 3
Ados.Position=(9-zimg(i))*320
Ados1.Position=i*320
Ados1.write ados.read(320)
next
Ados.LoadFromFile(Server.mappath("img_head.asp"))
Pos=lenb(Ados.read())
Ados.Position=Pos
for i=0 to 9 step 1
for j=0 to 3
Ados1.Position=i*32+j*320
Ados.Position=Pos+30*j+i*120
Ados.write ados1.read(30)
next
next
Response.ContentType = "image/BMP"
Ados.Position=0
Response.BinaryWrite Ados.read()
Ados.Close:set Ados=nothing
Ados1.Close:set Ados1=nothing
End Function
NumCode()
%>

md5.asp程序网上应该很多,用法如下,把这段程序做成一个单独文件,比如secret.asp,页面中调用为:
<img Src="secret.asp">这样就可以了,其实就是一个图象