how to use the differenceincalendarisoweeks function from date-fns in javascript

To use the differenceInCalendarISOWeeks function from the date-fns package in JavaScript, you need to first install the package using npm or yarn:

npm install date-fns
21 chars
2 lines

Once you have installed the package, you can import the differenceInCalendarISOWeeks function in your JavaScript file as follows:

index.tsx
import { differenceInCalendarISOWeeks } from 'date-fns';
57 chars
2 lines

The differenceInCalendarISOWeeks function takes two arguments - the start date and end date - and returns the difference in calendar ISO weeks between the two dates.

Here's an example:

index.tsx
import { differenceInCalendarISOWeeks } from 'date-fns';

const startDate = new Date('2022-01-01');
const endDate = new Date('2022-02-28');

const difference = differenceInCalendarISOWeeks(endDate, startDate);

console.log(difference); // output: 8
249 chars
9 lines

In the above example, we are calculating the difference in calendar ISO weeks between January 1st, 2022 and February 28th, 2022. The output of the function is 8, which means there are 8 ISO weeks between the two dates.