how to use the differenceinmilliseconds function from the date-fns library in typescript

To use differenceInMilliseconds function from date-fns library in TypeScript, first you need to install the library and its types:

npm install date-fns
npm install --save-dev @types/date-fns
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After installing, you can import the differenceInMilliseconds function like this:

index.ts
import { differenceInMilliseconds } from 'date-fns';
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You can then use this function to get the difference between two dates in milliseconds:

index.ts
const date1 = new Date('2022-01-01T12:00:00.000Z');
const date2 = new Date('2022-01-01T12:00:01.000Z');

const difference = differenceInMilliseconds(date2, date1);

console.log(difference); // Output: 1000
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Here, the differenceInMilliseconds function takes two parameters: the later date (date2 in this case) and the earlier date (date1 in this case). The function returns the difference between the two dates in milliseconds.

Note that the differenceInMilliseconds function only calculates the difference between full milliseconds, so any fractional milliseconds will be truncated.