我們經常在登陸時要讓用戶輸入個驗證碼，對於這個驗證碼的產生，有好幾種方法，有直接就是數字，那太簡單，還有的是由數字映射到相應的圖片，那樣又不大好，找了一下網上關於這方面的介紹，決定由程序生成一張圖片，圖片裏是驗證碼。
這裏又有２種方法，一種要其它組件，當然是不用組件的好了。
網上對於這方面的介紹也有不少，這裏再寫出來，是爲了方便。
首先生成圖片的文件爲validatepic.asp，代碼如下：
<%
Dim a(10,10)
a(0,1) = "0x3c" '數字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" '數字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" '數字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" '數字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" '數字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" '數字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" '數字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" '數字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" '數字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" '數字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"
%>
<%
'開啓緩衝Response.Buffer = True
With Response
.Expires = -1
.AddHeader "Pragma","no-cache"
.AddHeader "cache-ctrol","no-cache"
End With
Dim num
Randomize
num = Int(7999 * Rnd + 2000)
Session("validateCode") = num
Dim Image
Dim Width, Height
Dim digtal
Dim Length
Dim sort
Dim hc
Length = 4
hc = chr(13) & chr(10)
Redim sort(Length)
digital = ""
For I = 1 To Length - Len(num)
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)
Height = 10
Response.ContentType = "image/x-xbitmap"
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)
Image = Image & "};" & hc
Response.Write Image
%>
代碼就上面的了，這裏用到xbm數字圖片，這裏不做過多介紹，想進一步瞭解可以自己搜索。
顯示的時候，加上<img src="validatepic.asp.asp"></img>就可以了。