用ASP随机产生随机验证码

　　各位好今天我要告诉大家的是如何用ASP产生随机数。大家都知道大多数网站注册后提供用户名和一个随机密码，但这个密码是如何产生的，现在我就向大家来介绍一下

　　看下面的例子，用户可自行增加或减少随机的字符或数量。

<%
Function gen_key(digits)

'Create and define array
dim char_array(50)
char_array(0) = "0"
char_array(1) = "1"
char_array(2) = "2"
char_array(3) = "3"
char_array(4) = "4"
char_array(5) = "5"
char_array(6) = "6"
char_array(7) = "7"
char_array(8) = "8"
char_array(9) = "9"
char_array(10) = "A"
char_array(11) = "B"
char_array(12) = "C"
char_array(13) = "D"
char_array(14) = "E"
char_array(15) = "F"
char_array(16) = "G"
char_array(17) = "H"
char_array(18) = "I"
char_array(19) = "J"
char_array(20) = "K"
char_array(21) = "L"
char_array(22) = "M"
char_array(23) = "N"
char_array(24) = "O"
char_array(25) = "P"
char_array(26) = "Q"
char_array(27) = "R"
char_array(28) = "S"
char_array(29) = "T"
char_array(30) = "U"
char_array(31) = "V"
char_array(32) = "W"
char_array(33) = "X"
char_array(34) = "Y"
char_array(35) = "Z"

'Initiate randomize method for default seeding
randomize

'Loop through and create the output based on the the variable passed to
'the function for the length of the key.
do while len(output) < digits
num = char_array(Int((35 - 0 + 1) * Rnd + 0))
output = output + num
loop

'Set return
gen_key = output
End Function

'Write the results to the browser, currently setting a 13 digit key
response.write "<pre>" & gen_key(13) & "</pre>" & vbcrlf
%>