<%
Option Explicit
Response.buffer=true
Response.Expires = -1
Response.ExpiresAbsolute = Now() - 1

Call Com_CreatValidCode("checkcode")

Sub Com_CreatValidCode(pSN)
	'Author: Layen
	'QQ: 84815733
	'E-mail: support@ssaw.net
	' 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) = "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"
	' 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
					If Mid(vNumberData(vCode(ii)), i * 10 + iii, 1) Then
						Response.BinaryWrite vColorData(0)
					Else
						Response.BinaryWrite vColorData(1)
					End If
				Else
					Response.BinaryWrite vColorData(Mid(vNumberData(vCode(ii)), i * 10 + iii, 1))
				End If
			Next
		Next
	Next
End Sub
%>