<script language="JavaScript" type="text/JavaScript">
//str_0 长度
//str_1 是否大写字母
//str_2 是否小写字母
//str_3 是否数字
function rnd_str(str_0,str_1,str_2,str_3)
{
var Seed_array=new Array();
var seedary;
var i; Seed_array[0]=""
Seed_array[1]= "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z";
Seed_array[2]= "a b c d e f g h i j k l m n o p q r s t u v w x y z";
Seed_array[3]= "0 1 2 3 4 5 6 7 8 9";
if (!str_1&&!str_2&&!str_3){str_1=true;str_2=true;str_3=true;} if (str_1){Seed_array[0]+=Seed_array[1];}
if (str_2){Seed_array[0]+=" "+Seed_array[2];}
if (str_3){Seed_array[0]+=" "+Seed_array[3];} Seed_array[0]= Seed_array[0].split(" ");
seedary=""
for (i=0;i<str_0;i++)
{
seedary+=Seed_array[0][Math.round(Math.random( )*(Seed_array[0].length-1))]
}
return(seedary); } var tmp=rnd_str(6,true,true,true);
document.write(tmp);
</script>
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META http-equiv=Content-Type content="text/html; charset=gb2312">
<META NAME="Author" CONTENT="Seagle.K">
<STYLE TYPE="text/css"></STYLE>
<SCRIPT LANGUAGE="JavaScript">
function getrandom(len)
{
var seed = new Array(
'abcdefghijklmnopqrstuvwxyz',
'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
'0123456789'
);
var idx,i;
var result = '';
for (i=0; i<len; i++)
{
idx = Math.floor(Math.random()*3);
result += seed[idx].substr(Math.floor(Math.random()*(seed[idx].length)), 1);
} return result;
}
</SCRIPT>
</HEAD>
<BODY>
长度：
<SELECT id="sel">
<option value=1>1</option>
<option value=3>3</option>
<option value=5 selected>5</option>
<option value=7>7</option>
<option value=9>9</option>
</SELECT>
<BR>
生成：
<INPUT TYPE="text" id="txt">
<INPUT TYPE="button" VALUE=" GO " ONCLICK="txt.value=getrandom(sel.value)">
</BODY>
</HTML>
<SCRIPT LANGUAGE="JavaScript">
<!--
var s = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
var a = s.split("");
var n = Math.round(Math.random() * a.length);
alert(a[n]);
//-->
</SCRIPT>