將以下代碼放到一個單獨的頁面checkcode.asp
<%
Option Explicit
Response.buffer=true
Call Com_CreatValidCode("validateCode")
Sub Com_CreatValidCode(pSN)
' 禁止緩存
Response.Expires = -9999
Response.AddHeader "Pragma","no-cache"
Response.AddHeader "cache-ctrol","no-cache"
Response.ContentType = "Image/BMP"
Randomize
Dim i, ii, iii
Const cOdds = 2 ' 雜點出現的機率
Const cAmount = 10 ' 文字數量
Const cCode = "0123456789"
' 顏色的數據(字符，背景)
Dim vColorData(1)
vColorData(0) = ChrB(0) & ChrB(0) & ChrB(211) ' 藍0，綠0，紅0（黑色）
vColorData(1) = ChrB(255) & ChrB(255) & ChrB(255) ' 藍250，綠236，紅211（淺藍色）
' 隨機產生字符
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 '記錄入Session
' 字符的數據
Dim vNumberData(9)
vNumberData(0) =
"1110000111110111101111011110111101001011110100101111010010111101001011110111101111011110111
110000111"
vNumberData(1) =
"1111011111110001111111110111111111011111111101111111110111111111011111111101111111110111111
100000111"
vNumberData(2) =
"1110000111110111101111011110111111111011111111011111111011111111011111111011111111011110111
100000011"
vNumberData(3) =
"1110000111110111101111011110111111110111111100111111111101111111111011110111101111011110111
110000111"
vNumberData(4) =
"1111101111111110111111110011111110101111110110111111011011111100000011111110111111111011111
111000011"
vNumberData(5) =
"1100000011110111111111011111111101000111110011101111111110111111111011110111101111011110111
110000111"
vNumberData(6) =
"1111000111111011101111011111111101111111110100011111001110111101111011110111101111011110111
110000111"
vNumberData(7) =
"1100000011110111011111011101111111101111111110111111110111111111011111111101111111110111111
111011111"
vNumberData(8) =
"1110000111110111101111011110111101111011111000011111101101111101111011110111101111011110111
110000111"
vNumberData(9) =
"1110001111110111011111011110111101111011110111001111100010111111111011111111101111011101111
110001111"
' 輸出圖像文件頭
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)
' 輸出圖像信息頭
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 ' 歷經所有行
For ii = 0 To 3 ' 歷經所有字
For iii = 1 To 10 ' 歷經所有像素
' 逐行、逐字、逐像素地輸出圖像數據
If Rnd * 99 + 1 < cOdds Then ' 隨機生成雜點
Response.BinaryWrite vColorData(0)
Else
Response.BinaryWrite vColorData(Mid(vNumberData(vCode(ii)), i * 10 + iii, 1))
End If
Next
Next
Next
End Sub
%>
需要用得頁面用如下方式引用：
驗證碼： src="checkcode.asp " style="margin: 0px; padding: 0px; outline: none; line-height: 25.2px; font-size: 14px; width: 660px; overflow: hidden; clear: both; font-family: tahoma, arial, "Microsoft YaHei";">
<%
if trim(session("validateCode")) <> trim(Request("txt_check")) then
ErrorMessage = "請輸入正確的驗證碼"
response.write(" <script>alert('"&ErrorMessage&"');location.href='Default.asp' </script>")
response.end
end if
%>
