JavaScript automatically generates random strings containing numbers and characters_javascript skills

The example in this article describes how javascript can automatically generate a random string containing numbers and characters. Share it with everyone for your reference. The details are as follows:

The two functions Math.random() and Math.floor() are mainly used here

Math.random() -- Returns a pseudo-random number between 0 and 1. It may be 0, but it is always less than 1, [0,1)

Math.floor() -- round down and discard the decimal value

Method to implement random multi-digit numbers:

Copy code The code is as follows:

/**
*
* Randomly generated numbers
*
*@param num Number of generated digits
*/
function randomNumber(num){
           return '' Math.floor(Math.random() * num) ;
}

javascript randomly generates characters

The following examples are random characters appearing in the random A-Z / a-z range

Copy code The code is as follows:

/**
*
* Randomly generated
*
*@param data json data Example: {"start":0,"end":2,"number":5,"upper":true}
*@param start Start subscript
*@param end End subscript
*@param number Number of generated digits
*@param upper Whether it is uppercase or not. The default is lowercase
​*/
function randomLetter(data){
var letterData = "";
var lowercase = new Array("a","b","c","d","e","f","g","h","i","g","k", "l","m","n","o","p","q","r","s","t","u","v","w","x ","y","z");

var uppercase = new Array("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");
var start = data.start;
var end = data.end;
var number = data.number;
var upper = data.upper;

var length = end - start;
for(var i= 0;i < number; i ){
      var index = Math.floor(Math.random() * length) start;  
      var letter = "";  
If(upper){
             letter = uppercase[index];
          }else{ 
              letter = lowercase[index]; 
                                                                                                                            letterData = letter;                         }  
Return letterData;
}

Quote:

Copy code The code is as follows:alert(new Date().Format("yyyy-MM-dd hh:mm :ss"));

I hope this article will be helpful to everyone’s JavaScript programming design.