首页 > 代码库 > random随机数应用

random随机数应用

2024-09-19 21:06:36   225人阅读

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Title</title>
 6     <style type="text/css">
 7         *{
 8             margin:0;
 9             padding:0;
10         }
11         span{
12 
13             height: 20px;
14             line-height: 20px;
15             text-align: center;
16             background: gray;
17             color: #f0f0f0;
18         }
19         div{
20             width:100px;
21             height: 100px;
22             border:1px solid red;
23         }
24     </style>
25     <script type="text/javascript">
26         window.onload = function () {
27             //随机生成四位数字的验证码
28             var t = parseInt(Math.random()*8999+1000);
29             var spanNode = document.getElementsByTagName("span")[0];
30             spanNode.innerHTML = t;
31             //随机生成含有字母的验证码
32             //注意toString括号里的值，可以不写，不写默认的是10，小于10只会出现数字。大于10会出现字母
33             var b = Math.random().toString(36).substr(2);
34             var span1Node = document.getElementsByTagName("span")[1];
35             span1Node.innerHTML =b;
36             //利用随机函数使颜色随机变化
37             var r =Math.round(Math.random()*256)%255;
38             var g =Math.round(Math.random()*256)%255;
39             var b =Math.round(Math.random()*256)%255;
40             var rgbB = "rgb("+r+","+b +","+g+")";
41             document.body.style.background =rgbB;
42         }
43         //随机产生数组里包含的验证码
44         //randomFlag表示是否随机
45         //min随机字符的最小长度
46         //max随机字符的最大长度
47         function randomWord(randomFlag, min, max){
48             var str = "",
49                 range = min,
50                 arr = [‘0‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘, ‘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‘, ‘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‘];
51             // 随机产生
52             if(randomFlag){
53                 range = Math.round(Math.random() * (max-min)) + min;
54             }
55             for(var i=0; i<range; i++){
56                 pos = Math.round(Math.random() * (arr.length-1));
57                 str += arr[pos];
58             }
59             return str;
60         }
61         var g = randomWord(true, 3, 8);
62         document.write(g);
63     </script>
64 </head>
65 <body>
66 <form action="">
67     <h3>产生四位数字的随机验证码</h3>
68     <span></span>
69 <input type="submit" value="换一组">
70     <h3>产生包含字母的随机验证码</h3>
71     <span></span>
72     <input type="submit" value="换一组">
73 </form>
74 </body>
75 </html>

技术分享

random随机数应用


联系
我们