<%
Option Explicit
Response.buffer=true
NumCode
Function NumCode()
Response.Expires = -1
Response.AddHeader "Pragma","no-cache"
Response.AddHeader "cache-ctrol","no-cache"
On Error Resume Next
Dim zNum,i,j
Dim Ados,Ados1
Randomize timer
zNum = cint(8999*Rnd+1000)
Session("CheckCode") = 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("body.Fix"))
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("head.fix"))
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 = "images/BMP"
Ados.Position=0
Response.BinaryWrite Ados.read()
Ados.Close:set Ados=nothing
Ados1.Close:set Ados1=nothing
If Err Then Session("CheckCode") = 9999
End Function
%>
<img src="checkcode.asp">
判断用户输入是否正确:
if(form1.yanz.value<>.........)
{
alert("请输入正确的验证码")
return false;
}