一个很简单的验证码程序

主程序共三个

我的调用方式 <script language="javascript"
src="/verify/num.asp"></script>
验证方式 if
trim(Loginnum)<>trim(session("Loginnum")) then
Response.Write
Error("验证码错误！")
Response.End
end if

num.asp

<%
'### To encrypt/decrypt include this code in your page
'###
strMyEncryptedString = EncryptString(strString)
'### strMyDecryptedString =
DeCryptString(strMyEncryptedString)
'### You are free to use this code as
long as credits remain in place
'### also if you improve this code let me
know.

Private Function EncryptString(strString)

'####################################################################

'### Crypt Function ? 2001 by Slavic Kozyuk grindkore@yahoo.com ###
'###
Arguments: strString <--- String you wish to encrypt ###
'### Output:
Encrypted HEX string ###

'####################################################################

Dim CharHexSet, intStringLen, strTemp, strRAW, I, intKey, intOffSet

Randomize Timer

intKey = Round((RND * 1000000) + 1000000) '##### Key Bitsize
intOffSet =
Round((RND * 1000000) + 1000000) '##### KeyOffSet Bitsize

If IsNull(strString) = False Then
strRAW = strString
intStringLen =
Len(strRAW)

For i = 0 to intStringLen - 1
strTemp = Left(strRAW, 1)
strRAW =
Right(strRAW, Len(strRAW) - 1)
CharHexSet = CharHexSet &
Hex(Asc(strTemp) * intKey)& Hex(intKey)
Next

EncryptString = CharHexSet & "|" & Hex(intOffSet + intKey) & "|"
& Hex(intOffSet)
Else
EncryptString = ""
End If
End Function

Private Function DeCryptString(strCryptString)

'####################################################################

'### Crypt Function ? 2001 by Slavic Kozyuk grindkore@yahoo.com ###
'###
Arguments: Encrypted HEX stringt ###
'### Output: Decrypted ASCII string ###

'####################################################################

'### Note this function uses HexConv() and get_hxno() functions ###
'###
so make sure they are not removed ###

'####################################################################

Dim strRAW, arHexCharSet, I, intKey, intOffSet, strRawKey, strHexCrypData

strRawKey = Right(strCryptString, Len(strCryptString) -
InStr(strCryptString, "|"))
intOffSet = Right(strRawKey, Len(strRawKey) -
InStr(strRawKey,"|"))
intKey = HexConv(Left(strRawKey, InStr(strRawKey, "|")
- 1)) - HexConv(intOffSet)
strHexCrypData = Left(strCryptString,
Len(strCryptString) - (Len(strRawKey) + 1))

arHexCharSet = Split(strHexCrypData, Hex(intKey))

For i=0 to Ubound(arHexCharSet)
strRAW = strRAW &
Chr(HexConv(arHexCharSet(i))/intKey)
Next

DeCryptString = strRAW
End Function

Private Function HexConv(hexVar)
Dim hxx, hxx_var, multiply
IF hexVar
<> "" THEN
hexVar = UCASE(hexVar)
hexVar = StrReverse(hexVar)

DIM hx()
REDIM hx(LEN(hexVar))
hxx = 0
hxx_var = 0
FOR hxx =
1 TO LEN(hexVar)
IF multiply = "" THEN multiply = 1
hx(hxx) =
mid(hexVar,hxx,1)
hxx_var = (get_hxno(hx(hxx)) * multiply) + hxx_var

multiply = (multiply * 16)
NEXT
hexVar = hxx_var
HexConv =
hexVar
END IF
End Function

Private Function get_hxno(ghx)
If ghx = "A" Then
ghx = 10
ElseIf
ghx = "B" Then
ghx = 11
ElseIf ghx = "C" Then
ghx = 12
ElseIf
ghx = "D" Then
ghx = 13
ElseIf ghx = "E" Then
ghx = 14
ElseIf
ghx = "F" Then
ghx = 15
End If
get_hxno = ghx
End Function

randomize
num = int(7999*rnd+2000) '计数器的值
num2 = EncryptString(num)

session("Loginnum")=num
%>
document.write("<img
src='/verify/count.asp?sksid=<%=num2%>'>") ' 这里是调用图片的路径

count.asp

<!--#include file="numimg.asp"-->

<%
'### To encrypt/decrypt include this code in your page
'###
strMyEncryptedString = EncryptString(strString)
'### strMyDecryptedString =
DeCryptString(strMyEncryptedString)
'### You are free to use this code as
long as credits remain in place
'### also if you improve this code let me
know.

Private Function EncryptString(strString)

'####################################################################

'### Crypt Function ? 2001 by Slavic Kozyuk grindkore@yahoo.com ###
'###
Arguments: strString <--- String you wish to encrypt ###
'### Output:
Encrypted HEX string ###

'####################################################################

Dim CharHexSet, intStringLen, strTemp, strRAW, I, intKey, intOffSet

Randomize Timer

intKey = Round((RND * 1000000) + 1000000) '##### Key Bitsize
intOffSet =
Round((RND * 1000000) + 1000000) '##### KeyOffSet Bitsize

If IsNull(strString) = False Then
strRAW = strString
intStringLen =
Len(strRAW)

For i = 0 to intStringLen - 1
strTemp = Left(strRAW, 1)
strRAW =
Right(strRAW, Len(strRAW) - 1)
CharHexSet = CharHexSet &
Hex(Asc(strTemp) * intKey)& Hex(intKey)
Next

EncryptString = CharHexSet & "|" & Hex(intOffSet + intKey) & "|"
& Hex(intOffSet)
Else
EncryptString = ""
End If
End Function

Private Function DeCryptString(strCryptString)

'####################################################################

'### Crypt Function ? 2001 by Slavic Kozyuk grindkore@yahoo.com ###
'###
Arguments: Encrypted HEX stringt ###
'### Output: Decrypted ASCII string ###

'####################################################################

'### Note this function uses HexConv() and get_hxno() functions ###
'###
so make sure they are not removed ###

'####################################################################

Dim strRAW, arHexCharSet, I, intKey, intOffSet, strRawKey, strHexCrypData

strRawKey = Right(strCryptString, Len(strCryptString) -
InStr(strCryptString, "|"))
intOffSet = Right(strRawKey, Len(strRawKey) -
InStr(strRawKey,"|"))
intKey = HexConv(Left(strRawKey, InStr(strRawKey, "|")
- 1)) - HexConv(intOffSet)
strHexCrypData = Left(strCryptString,
Len(strCryptString) - (Len(strRawKey) + 1))

arHexCharSet = Split(strHexCrypData, Hex(intKey))

For i=0 to Ubound(arHexCharSet)
strRAW = strRAW &
Chr(HexConv(arHexCharSet(i))/intKey)
Next

DeCryptString = strRAW
End Function

Private Function HexConv(hexVar)
Dim hxx, hxx_var, multiply
IF hexVar
<> "" THEN
hexVar = UCASE(hexVar)
hexVar = StrReverse(hexVar)

DIM hx()
REDIM hx(LEN(hexVar))
hxx = 0
hxx_var = 0
FOR hxx =
1 TO LEN(hexVar)
IF multiply = "" THEN multiply = 1
hx(hxx) =
mid(hexVar,hxx,1)
hxx_var = (get_hxno(hx(hxx)) * multiply) + hxx_var

multiply = (multiply * 16)
NEXT
hexVar = hxx_var
HexConv =
hexVar
END IF
End Function

Private Function get_hxno(ghx)
If ghx = "A" Then
ghx = 10
ElseIf
ghx = "B" Then
ghx = 11
ElseIf ghx = "C" Then
ghx = 12
ElseIf
ghx = "D" Then
ghx = 13
ElseIf ghx = "E" Then
ghx = 14
ElseIf
ghx = "F" Then
ghx = 15
End If
get_hxno = ghx
End Function

%>

<%
Dim Image
Dim Width, Height
Dim num
Dim digtal

Dim Length
Dim sort
Length = 4 '自定计数器长度

Redim sort( Length )

num=cint(DeCryptString(request.querystring("sksid")))
digital = ""

For I = 1 To Length -Len( num ) '补0
digital = digital & "0"
Next

For I = 1 To Len( num )
digital = digital & Mid( num, I, 1 )

Next
For I = 1 To Len( digital )
sort(I) = Mid( digital, I, 1 )

Next
Width = 8 * Len( digital ) '图像的宽度
Height = 10 '图像的高度，在本例中为固定值

Response.ContentType="image/x-xbitmap"

hc=chr(13) & chr(10)

Image = "#define counter_width " & Width & hc
Image = Image &
"#define counter_height " & Height & hc
Image = Image & "static
unsigned char counter_bits[]={" & hc

For I = 1 To Height
For J = 1 To Length
Image = Image &
a(sort(J),I) & ","
Next
Next

Image = Left( Image, Len( Image ) - 1 ) '去掉最后一个逗号
Image = Image &
"};" & hc
%>
<%
Response.Write Image

%>

numimg.asp

<%
Dim a(10,10)

a(0,1) = "0x3c" '数字0
a(0,2) = "0x66"
a(0,3) = "0xc3"
a(0,4) =
"0xc3"
a(0,5) = "0xc3"
a(0,6) = "0xc3"
a(0,7) = "0xc3"
a(0,8) =
"0xc3"
a(0,9) = "0x66"
a(0,10)= "0x3c"

a(1,1) = "0x18" '数字1
a(1,2) = "0x1c"
a(1,3) = "0x18"
a(1,4) =
"0x18"
a(1,5) = "0x18"
a(1,6) = "0x18"
a(1,7) = "0x18"
a(1,8) =
"0x18"
a(1,9) = "0x18"
a(0,10)= "0x7e"

a(2,1) = "0x3c" '数字2
a(2,2) = "0x66"
a(2,3) = "0x60"
a(2,4) =
"0x60"
a(2,5) = "0x30"
a(2,6) = "0x18"
a(2,7) = "0x0c"
a(2,8) =
"0x06"
a(2,9) = "0x06"
a(2,10)= "0x7e"

a(3,1) = "0x3c" '数字3
a(3,2) = "0x66"
a(3,3) = "0xc0"
a(3,4) =
"0x60"
a(3,5) = "0x1c"
a(3,6) = "0x60"
a(3,7) = "0xc0"
a(3,8) =
"0xc0"
a(3,9) = "0x66"
a(3,10)= "0x38"

a(4,1) = "0x38" '数字4
a(4,2) = "0x3c"
a(4,3) = "0x36"
a(4,4) =
"0x33"
a(4,5) = "0x33"
a(4,6) = "0x33"
a(4,7) = "0xff"
a(4,8) =
"0x30"
a(4,9) = "0x30"
a(4,10)= "0xfe"

a(5,1) = "0xfe" '数字5
a(5,2) = "0xfe"
a(5,3) = "0x06"
a(5,4) =
"0x06"
a(5,5) = "0x3e"
a(5,6) = "0x60"
a(5,7) = "0xc0"
a(5,8) =
"0xc3"
a(5,9) = "0x66"
a(5,10)= "0x3c"

a(6,1) = "0x60" '数字6
a(6,2) = "0x30"
a(6,3) = "0x18"
a(6,4) =
"0x0c"
a(6,5) = "0x3e"
a(6,6) = "0x63"
a(6,7) = "0xc3"
a(6,8) =
"0xc3"
a(6,9) = "0x66"
a(6,10) ="0x3c"

a(7,1) = "0xff" '数字7
a(7,2) = "0xc0"
a(7,3) = "0x60"
a(7,4) =
"0x30"
a(7,5) = "0x18"
a(7,6) = "0x18"
a(7,7) = "0x18"
a(7,8) =
"0x18"
a(7,9) = "0x18"
a(7,10)= "0x18"

a(8,1) = "0x3c" '数字8
a(8,2) = "0x66"
a(8,3) = "0xc3"
a(8,4) =
"0x66"
a(8,5) = "0x3c"
a(8,6) = "0x66"
a(8,7) = "0xc3"
a(8,8) =
"0xc3"
a(8,9) = "0x66"
a(8,10)= "0x3c"

a(9,1) = "0x3c" '数字9
a(9,2) = "0x66"
a(9,3) = "0xc3"
a(9,4) =
"0xc3"
a(9,5) = "0x66"
a(9,6) = "0x3c"
a(9,7) = "0x18"
a(9,8) =
"0x0c"
a(9,9) = "0x06"
a(9,10)= "0x03"

%>