how to use the formatrfc3339 function from the date-fns library in typescript

To use the formatRFC3339 function from the date-fns library in TypeScript, you first need to import it from the library:

index.ts
import { formatRFC3339 } from 'date-fns';
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Then, you can call the function with a date object to format it into an RFC 3339 string:

index.ts
const myDate = new Date();
const rfc3339String = formatRFC3339(myDate);
console.log(rfc3339String); // Output: 2021-05-24T14:30:00.000Z
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The formatRFC3339 function can also take an optional additionalDigits parameter, which specifies the precision of the seconds in the output string. The default value is 3, which includes milliseconds, but you can set it to 0 to exclude milliseconds:

index.ts
const myDate = new Date();
const rfc3339String = formatRFC3339(myDate, { additionalDigits: 0 });
console.log(rfc3339String); // Output: 2021-05-24T14:30:00Z
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Note that the formatRFC3339 function returns a string in the UTC timezone with a "Z" at the end to indicate the timezone offset. If you need to display the date in a different timezone, you can use the utcToZonedTime function from the date-fns-tz library to convert the date object to a timezone-specific date object before formatting it with formatRFC3339.