JavaScript generates one-time password (OTP)

A one-time password (OTP) is a password that is valid for only one login session or transaction on a computer or digital device. Nowadays, almost all services such as online banking and online transactions use OTP. They are usually a combination of 4 or 6 digits or 6 alphanumeric digits. The random function is used to generate random OTPs predefined in the math library. This article will introduce to you how to use JavaScript to generate OTP. (Recommended: "javascript tutorial")

Function:

##random():This function returns 0 to 1 any random number between.

floor():It returns the floor of any floating point number as an integer value.

Use the function above to select a random index of the string array that contains all possible candidates for a specific number of OTP.

Example 1: Generate 4-digit OTP:

<script> 
  
function generateOTP() { 
          
    // 声明一个存储所有数字的digits变量
    var digits = &#39;0123456789&#39;; 
    let OTP = &#39;&#39;; 
    for (let i = 0; i < 4; i++ ) { 
        OTP += digits[Math.floor(Math.random() * 10)]; 
    } 
    return OTP; 
} 
  
document.write("4位OTP: ") 
document.write( generateOTP() ); 
</script>

Output:

4位OTP: 2229

Example 2: Generate 6-digit number OTP:

<script> 
  
function generateOTP() { 
          
    var digits = &#39;0123456789&#39;; 
    let OTP = &#39;&#39;; 
    for (let i = 0; i < 6; i++ ) { 
        OTP += digits[Math.floor(Math.random() * 10)]; 
    } 
    return OTP; 
} 
  
document.write("6位OTP: ") 
document.write( generateOTP() ); 
</script>

Output:

6位OTP: 216664

Example 3: Generate alphanumeric OTP of length 6:

<script> 
  
function generateOTP() { 
          
    //声明一个存储所有字符串的string变量
    var string = &#39;0123456789abcdefghijklmnopqrs 
    tuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ&#39;; 
    let OTP = &#39;&#39;; 
      
    //求字符串的长度
    var len = string.length; 
    for (let i = 0; i < 6; i++ ) { 
        OTP += string[Math.floor(Math.random() * len)]; 
    } 
    return OTP; 
} 
  
document.write("长度为6的OTP: ") 
document.write( generateOTP() ); 
</script>

Output :

长度为6的OTP: rab0Tj

This article is a specific introduction to JavaScript to generate one-time passwords (OTP). I hope it will be helpful to friends in need!

The above is the detailed content of JavaScript generates one-time password (OTP). For more information, please follow other related articles on the PHP Chinese website!