JS中产生20位随机数以0-9为例也可以是a-z A-Z
JS代码：
functions20(){
vardata=["0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"];
for(varj=0;j<500;j++){//500为想要产生的行数
varresult="";
for(vari=0;i<20;i++){//产生20位就使i<20
r=Math.floor(Math.random()*16);//16为数组里面数据的数量，目的是以此当下标取数组data里的值！
result+=data[r];//输出20次随机数的同时，让rrr加20次，就是20位的随机字符串了。
}
document.write(result);
document.write("<br/>");
}}
完整html代码：
<html>
<head>
<metahttp-equiv="Content-Type"content="text/html;charset=utf-8"/>
<title></title>
<scripttype="text/javascript">
functions20(){
vardata=["0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"];
for(varj=0;j<500;j++){
varresult="";
for(vari=0;i<20;i++){
r=Math.floor(Math.random()*16);
result+=data[r];
}
document.write(result);
document.write("<br/>");
}}
</script>
</head>
<body>
<inputtype="button"onclick="s20()"value="产生随机数">
</body>
</html>