Extracting, Adding, and Formatting Days with date-fns

1. Date Object
   "date-fns" primarily works with standard JavaScript Date objects. These objects contain information about a specific date and time.

2. Extracting Day Information
   Several functions in "date-fns" allow you to extract the day information from a Date object. These functions return a number representing the day of the month (1-31). Here are some examples:

   • getDate(date): This function returns the day of the month for a given date object.

3. Manipulating Days
   "date-fns" provides functions to manipulate dates by specific day increments. For instance:

   • addDays(date, amount): This function adds a specified number of days to a date object and returns a new Date object.

4. Formatting with Day
   While not a specific type, "date-fns" offers formatting functions that can include the day information in the output. For example:

   • format(date, 'dd/MM/yyyy'): This function formats the date object as "day/month/year".

In summary

• Functions exist to extract day information, manipulate dates by days, and format dates including the day.
• "date-fns" doesn't have a dedicated "Day" type, but it works with JavaScript Date objects.

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Extracting Day of the Month

const today = new Date();

// Get the day of the month (1-31)
const day = dateFns.getDate(today);
console.log("Day of the month:", day);

Adding or Subtracting Days

const vacationStart = new Date(2024, 5, 10); // June 10th, 2024

// Add 3 days to the vacation start date
const vacationEnd = dateFns.addDays(vacationStart, 3);
console.log("Vacation end date:", vacationEnd);

// Subtract 7 days from today
const oneWeekAgo = dateFns.subDays(new Date(), 7);
console.log("One week ago:", oneWeekAgo);

const upcomingMeeting = new Date(2024, 5, 28); // May 28th, 2024

// Format the date with day, month, and year
const formattedDate = dateFns.format(upcomingMeeting, "EEEE, MMMM do, yyyy");
console.log("Formatted meeting date:", formattedDate); // Output: Tuesday, May 28th, 2024

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Native JavaScript Date Object

const today = new Date();

// Get day of the month
const day = today.getDate();
console.log("Day of the month:", day);

// Add 3 days
const vacationStart = new Date(2024, 5, 10);
vacationStart.setDate(vacationStart.getDate() + 3);
console.log("Vacation end date:", vacationStart);

// Format with day, month, and year (requires additional manipulation)
const upcomingMeeting = new Date(2024, 5, 28);
const options = { weekday: 'long', month: 'long', day: 'numeric', year: 'numeric' };
const formattedDate = upcomingMeeting.toLocaleDateString('en-US', options);
console.log("Formatted meeting date:", formattedDate);

Moment.js Library

Moment.js is another popular library for date and time manipulation in JavaScript. It offers a rich set of features similar to "date-fns" with a slightly different syntax. You'd need to include the Moment.js library in your project to use it.

Third-party Libraries

Several other libraries like Luxon or Day.js provide alternative functionalities for date and time manipulation in JavaScript. Explore these options if "date-fns" doesn't suit your specific needs.