asp 如何实现验证码

[wcfboy1]

ASP 验证码功能是如何实现的？请教大家 给个最简单的方法

[TSD]

随机生成一组数字或字符，然后再生成图片

论坛里有很多这样的贴，搜索一下就OK

[笨笨兔兔兔兔兔]

代码多多,这个是昨天xingyunyishui 给的
<%
Call Com_CreatValidCode("ValidCode")

Sub Com_CreatValidCode(pSN)

'Author: Layen
'QQ: 84815733
'E-mail: [e-mail]

' 禁止缓存
Response.Expires = -9999
Response.AddHeader "Pragma","no-cache"
Response.AddHeader "cache-ctrol","no-cache"
Response.ContentType = "Image/BMP"
response.addheader "Content-Disposition", "inline; filename=test"

Randomize

Dim i, ii, iii

Const cOdds = 0 ' 杂点出现的机率
Const cAmount = 36 ' 文字数量
Const cCode = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"

' 颜色的数据(字符，背景)
Dim vColorData(1)
vColorData(0) = ChrB(0) & ChrB(0) & ChrB(0) ' 蓝0，绿0，红0（黑色）
vColorData(1) = ChrB(250) & ChrB(236) & ChrB(211) ' 蓝250，绿236，红211（浅蓝色）

' 随机产生字符
Dim vCode(4), vCodes
For i = 0 To 3
vCode(i) = Int(Rnd * cAmount)
vCodes = vCodes & Mid(cCode, vCode(i) + 1, 1)
Next

Session(pSN) = vCodes '记录入Session

' 字符的数据
Dim vNumberData(35)
vNumberData(0) = "1110000111110111101111011110111101001011110100101111010010111101001011110111101111011110111110000111"
vNumberData(1) = "1111011111110001111111110111111111011111111101111111110111111111011111111101111111110111111100000111"
vNumberData(2) = "1110000111110111101111011110111111111011111111011111111011111111011111111011111111011110111100000011"
vNumberData(3) = "1110000111110111101111011110111111110111111100111111111101111111111011110111101111011110111110000111"
vNumberData(4) = "1111101111111110111111110011111110101111110110111111011011111100000011111110111111111011111111000011"
vNumberData(5) = "1100000011110111111111011111111101000111110011101111111110111111111011110111101111011110111110000111"
vNumberData(6) = "1111000111111011101111011111111101111111110100011111001110111101111011110111101111011110111110000111"
vNumberData(7) = "1100000011110111011111011101111111101111111110111111110111111111011111111101111111110111111111011111"
vNumberData(8) = "1110000111110111101111011110111101111011111000011111101101111101111011110111101111011110111110000111"
vNumberData(9) = "1110001111110111011111011110111101111011110111001111100010111111111011111111101111011101111110001111"
vNumberData(10) = "1111011111111101111111101011111110101111111010111111101011111100000111110111011111011101111000100011"
vNumberData(11) = "1000000111110111101111011110111101110111110000111111011101111101111011110111101111011110111000000111"
vNumberData(12) = "1110000011110111101110111110111011111111101111111110111111111011111111101111101111011101111110001111"
vNumberData(13) = "1000001111110111011111011110111101111011110111101111011110111101111011110111101111011101111000001111"
vNumberData(14) = "1000000111110111101111011011111101101111110000111111011011111101101111110111111111011110111000000111"
vNumberData(15) = "1000000111110111101111011011111101101111110000111111011011111101101111110111111111011111111000111111"
vNumberData(16) = "1110000111110111011110111101111011111111101111111110111111111011100011101111011111011101111110001111"
vNumberData(17) = "1000100011110111011111011101111101110111110000011111011101111101110111110111011111011101111000100011"
vNumberData(18) = "1100000111111101111111110111111111011111111101111111110111111111011111111101111111110111111100000111"
vNumberData(19) = "1110000011111110111111111011111111101111111110111111111011111111101111111110111110111011111000011111"
vNumberData(20) = "1000100011110111011111011011111101011111110001111111010111111101101111110110111111011101111000100011"
vNumberData(21) = "1000111111110111111111011111111101111111110111111111011111111101111111110111111111011110111000000011"
vNumberData(22) = "1000100011110010011111001001111100100111110101011111010101111101010111110101011111010101111001010011"
vNumberData(23) = "1000100011110011011111001101111101010111110101011111010101111101100111110110011111011001111000110111"
vNumberData(24) = "1110001111110111011110111110111011111011101111101110111110111011111011101111101111011101111110001111"
vNumberData(25) = "1000000111110111101111011110111101111011110000011111011111111101111111110111111111011111111000111111"
vNumberData(26) = "1110001111110111011110111110111011111011101111101110111110111011111011101001101111011001111110001011"
vNumberData(27) = "1000001111110111011111011101111101110111110000111111010111111101101111110110111111011101111000110011"
vNumberData(28) = "1110000011110111101111011110111101111111111001111111111001111111111011110111101111011110111100000111"
vNumberData(29) = "1000000011101101101111110111111111011111111101111111110111111111011111111101111111110111111110001111"
vNumberData(30) = "1000100011110111011111011101111101110111110111011111011101111101110111110111011111011101111110001111"
vNumberData(31) = "1000100011110111011111011101111101110111111010111111101011111110101111111010111111110111111111011111"
vNumberData(32) = "1001010011110101011111010101111101010111110101011111001001111110101111111010111111101011111110101111"
vNumberData(33) = "1000100011110111011111101011111110101111111101111111110111111110101111111010111111011101111000100011"
vNumberData(34) = "1000100011110111011111011101111110101111111010111111110111111111011111111101111111110111111110001111"
vNumberData(35) = "1100000011110111011111111101111111101111111110111111110111111111011111111011111111101110111100000011"

' 输出图像文件头
Response.BinaryWrite ChrB(66) & ChrB(77) & ChrB(230) & ChrB(4) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) &_
ChrB(0) & ChrB(0) & ChrB(54) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(40) & ChrB(0) &_
ChrB(0) & ChrB(0) & ChrB(40) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(10) & ChrB(0) &_
ChrB(0) & ChrB(0) & ChrB(1) & ChrB(0)

' 输出图像信息头
Response.BinaryWrite ChrB(24) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(176) & ChrB(4) &_
ChrB(0) & ChrB(0) & ChrB(18) & ChrB(11) & ChrB(0) & ChrB(0) & ChrB(18) & ChrB(11) &_
ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0) &_
ChrB(0) & ChrB(0)

For i = 9 To 0 Step -1 ' 历经所有行
For ii = 0 To 3 ' 历经所有字
For iii = 1 To 10 ' 历经所有像素
' 逐行、逐字、逐像素地输出图像数据
If Rnd * 99 + 1 < cOdds Then ' 随机生成杂点
Response.BinaryWrite vColorData(0)
Else
Response.BinaryWrite vColorData(Mid(vNumberData(vCode(ii)), i * 10 + iii, 1))
End If
Next
Next
Next

End Sub
%>

[wangyingdong]

在网上搜一下就有很多`

[hbhbhbhbhb1021]

TSD升星星拉，验证码就是随即生成一组数，然后设个session和用户提交上来的字符串进行匹配，一样就验证通过，否则失败。网上流行很多，你找下现成代码。有一种验证在XP是不能显示的，要写个注册表导入的。
建议你可以参考竹竹验证码，无组件验证码，动网论坛验证码

[AntinomyArt]

Search

[lstup]

需要4个文件。两个是图片信息文件，两个ASP文件！

验证码图片信息文件： http://www.37zz.com/ShowPost.asp?id=99（因为CSDN不能传文件的，所以我传到我论坛上了！）

在调用的页面头部插入文件<!--#include file="getcode01.asp"-->
然后在需要插入验证码的地方插入<%=getcode()%>


GetCode.asp文件内容：

<%
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("GetCode") = 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("images/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("images/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 = "image/BMP"
Ados.Position=0
Response.BinaryWrite Ados.read()
Ados.Close:set Ados=nothing
Ados1.Close:set Ados1=nothing
If Err Then Session("GetCode") = 9999
End Function

%>

GetCode1.asp文件：

<%Function getcode1()
Dim test
On Error Resume Next
Set test=Server.CreateObject("Adodb.Stream")
Set test=Nothing
If Err Then
Dim code
Randomize timer
code = cint(8999*Rnd+1000)
Session("GetCode") = code
getcode1= Session("GetCode")
Else
getcode1= "<img src=""getcode.asp"">"
End If
End Function
%>

[「已注销」]

http://community.csdn.net/Expert/topic/3847/3847668.xml?temp=.195614

[mayi545]

N多