This example describes how JavaScript automatically generates random strings that contain numbers and characters. Share to everyone for your reference. Specifically as follows:
The main use here is Math.random () and Math.floor () two functions
Math.random ()--Returns a pseudo-random number between 0 and 1 that may be 0, but always less than 1,[0,1
Math.floor ()--rounding down, dropping the value of a small number
A method for implementing random numbers of digits:
Copy Code code as follows:
/**
*
* Randomly generated numbers
*
* Number of digits generated @param num
*/
function Randomnumber (num) {
Return ' +math.floor (math.random () * num);
}
JavaScript randomly generated characters
The following example is a random character that appears randomly in a-z/A-Z interval
Copy Code code as follows:
/**
*
* Random Generation
*
* @param Data JSON example: {"Start": 0, "End": 2, "number": 5, "Upper": true}
* @param start subscript
* @param end Subscript
* @param number generated digits
* @param Upper is uppercase default to 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;
}
Reference:
Copy Code code as follows:
Alert (new Date (). Format ("Yyyy-mm-dd hh:mm:ss"));
I hope this article will help you with your JavaScript programming.