This article mainly introduces how to generate random numbers in JS and provides related functions, if you are interested, you can refer to the following functions to introduce random numbers:
Var Rand = Math. random ();
- 1. Math. random (); the result is a random number (including 0, not 1) between 0 and 1)
- 2. Math. floor (num); The num parameter is a numerical value, and the function result is an integer part of num.
- 3. Math. round (num); The num parameter is a numerical value, and the function result is an integer rounded to num.
Math:Mathematical object that provides mathematical calculation of data.
Math. random ();Returns a random number between 0 and 1 (including 0, excluding 1.
Math. ceil (n );Returns the smallest integer greater than or equal to n.
UseMath. ceil (Math. random () * 10 );Obtain a random integer ranging from 1 to 10. The probability of getting 0 is very small.
Math. round (n );Returns the integer value after n rounding.
UseMath. round (Math. random ());Returns a random integer ranging from 0 to 1.
UseMath. round (Math. random () * 10 );You can obtain a random integer ranging from 0 to 10 in a balanced manner. The probability of obtaining a minimum value of 0 and a maximum value of 10 is less than half.
Math. floor (n );Returns the largest integer less than or equal to n.
UseMath. floor (Math. random () * 10 );You can obtain random integers ranging from 0 to 9 in a balanced manner.
The random lottery can also be expanded. For example, you can set the probability of a lottery and use it with the database.
// Demand for the probability of winning, 100% winning, three prizes, but the probability of getting a book is 20% function draw () {var d_s = GetRandom (100 ); if (d_s> = 1 & d_s <= 40) {alert ('Congratulations, you have drawn XXX! ');} Else if (d_s> = 41 & d_s <= 80) {alert ('Congratulations, you have drawn XXX! ');} Else {alert (' congratulations, you have obtained the book! ');}}
Function Code for generating random numbers in the corresponding js:
《script》 2function GetRandomNum(Min,Max){ var Range = Max - Min; var Rand = Math.random(); return(Min + Math.round(Rand * Range)); } 8var num = GetRandomNum(1,10); 9alert(num); 《script》var chars = ['0','1','2','3','4','5','6','7','8','9','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'];function generateMixed(n) { var res = ""; for(var i = 0; i < n ; i ++) { var id = Math.ceil(Math.random()*35); res += chars[id]; } return res;}
The above is the detailed content of this article, hoping to help you learn.