JavaScript automatically generates random strings containing numbers and characters

This article describes the method of automatically generating random strings containing numbers and characters in JavaScript. Share it for your reference. The details are as follows:

Here we mainly use two functions: Math.random() and Math.floor()

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

Math.floor() -- round down and discard the value after the small number

Methods to implement random multi-digit numbers:

Copy the code as follows:/**

*

* Randomly generated numbers

*

*@param num generates the number of digits

*/

function randomNumber(num){

return ''+Math.floor(Math.random() * num) ;

}

javascript randomly generated characters

The following example is a random character that appears in the random AZ/az interval

Copy the code as follows:/**

*

* Random generation

*

*@param data json data example: {"start":0,"end":2,"number":5,"upper":true}

*@param start subscript

*@param end subscript

*@param number generates the number of bits

*@param upper Whether the uppercase is lowercase by default

*/

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","v","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:

The code copy 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.