Javascript 随机验证码 

 1 <!DOCTYPE html>
 2 <html>
 3 <head lang="en">
 4 <meta charset="UTF-8">
 5 <title>随机验证码</title>
 6 </head>
 7 <body>
 8 <span id="msg"></span>
 9 <input type="button" value="刷新" onclick="show()">
10 <script>
11 function validateCode(n){
12     var s="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
13     var ret="";
14     for(var i=0;i<n;i++){
15     var index=Math.floor(Math.random()*62);
16     ret+= s.charAt(index);
17     // alert(Math.floor(Math.random()*62));
18     }
19     return ret;
20 }
21 function show(){
22     document.getElementById("msg").innerHTML=validateCode(5);
23 }
24 function renovates(){
25     document.location.reload();
26 }
27 window.onload=show;
28 </script>
29 </body>
30 </html>

 

posted @ 2017-08-21 14:05  wǒの湁茡潞釦﹌  阅读(147)  评论(0)    收藏  举报