这个程序主要是先生成一个随机数,然后根据生成的随机数经过变换后作为xbm图片的内容,最后显示这个图片. 验证时中要获取输入的数字和session(“validatecode”)比较,如果相等则通过验证(还要注意一下相比较的两数据的类型保持一致)。
如何显示生成的图片呢? <img src=”xbm.asp”></img>
关于xbm图的格式信息,看这里
http://www.zdnet.com.cn/developer/tech/story/0,2000081602,39134972,00.htm
xbm.asp的代码如下
程序代码:
<!–#include file=”numcode.asp”–>
<%
开启缓冲
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
%>
numcode.asp的代码如下:
程序代码:
<%
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”
%>