The hook situation

There may be many cases in which we want to generate a random number and in JavaScript we can do this by using the Math.random() function.

Generating random numbers in JavaScript is not as intuitive as it is in other languages as the Math.random() function only generates a floating-point number between 0 - 1. We often want to specify our own range and thus this snippet helps you do that.

Note

By default the Math.random() function is exclusive meaning that it includes the lower bound number but excludes the upper bound number. For example using Math.random() function will generates a floating-point number between 0 - 1 but not including 1. Therefore, the number that is generated will never be 1.

The getRandomNumber function, mimics the Math.random() function as by default getRandomNumber is exclusive.

How to use the getRandomNumber Function

The getRandomNumber function has three parameters:

1. A minimum value
2. A maximum value
3. An inclusivivity parameter which is a boolean

I've added an inclusivivity parameter that allows you to specifiy if you want to include or exclude the max number. By default this inclusivivity parameter is set to false, therefore, it will act like the normal Math.random() function and generate a random number from the minimum value to the maximum value but not including the maximum value. By setting the inclusivivity parameter to true, the getRandomNumber function will generate a random number from the minimum value to the maximum value and will include the maximum value.

const getRandomNumber = (min, max, inclusive = false) => {
  if (!inclusive) return Math.floor(Math.random() * (max - min) + min);

  return Math.floor(Math.random() * (max - min + 1) + min);
};

import getRandomNumber from "./getRandomNumber";

const min = 1;
const max = 500;
const includeMaxNumber = true;

const randomNumber = getRandomNumber(min, max, includeMaxNumber);