JS implements random generation of verification code

JS implements random generation of verification code

This article example shares the specific code of JS to achieve random generation of verification codes for your reference. The specific content is as follows

<!DOCTYPE html>
<html>
 <head>
  <meta charset="utf-8" />
  <title></title>
  <style>   
  </style>
 </head>
 <body>
  <div>
  <h1>111111</h1><a href="#" rel="external nofollow" >Can't see clearly, change one</a>
  </div>
  Verification code: <input type="text" value="" />
  <button>OK</button>
 </body>
 <script>
  var arr = ["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",
       0,1,2,3,4,5,6,7,8,9];
        var h1=document.querySelector("h1");
        var btn = document.querySelector("button");
        var change = document.querySelector("a");     
        var input = document.querySelector("input");         
         function fn(){
        var arr1=Math.floor(Math.random()*62);
        var arr2 = Math.floor(Math.random()*62);
        var arr3 = Math.floor(Math.random()*62);
        var arr4=Math.floor(Math.random()*62);
        var arr5=Math.floor(Math.random()*62);
        var arr6=Math.floor(Math.random()*62);
        var yz=""+arr[arr1]+arr[arr2]+arr[arr3]+arr[arr4]+arr[arr5]+arr[arr6];
            h1.innerHTML=yz;    
            btn.onclick=function(){
              alert(input.value);
             if(input.value==yz){
            alert("correct");
            }else{
             alert("error");
            }
           
            }
         }
        fn();
    change.addEventListener("click",fn);
 </script>
</html>

1. Math.floor() method

Math.floor(x)

The floor() method returns the largest integer less than or equal to x.

If the argument passed is an integer, the value is unchanged.

2. Math.random() method

The random() method returns a random number between 0 (inclusive) and 1 (exclusive).

The above two methods can be used to realize the function of taking random numbers

The above is the full content of this article. I hope it will be helpful for everyone’s study. I also hope that everyone will support 123WORDPRESS.COM.

You may also be interested in:
  • JavaScript implements random generation of verification code and verification
  • JavaScript implements the generation of 4-digit random verification code
  • JavaScript clicks the button to generate a 4-digit random verification code
  • JavaScript function encapsulates random color verification code (complete code)

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