Working with dates in JavaScript can be challenging, especially when you need to calculate the difference between two dates, excluding weekends. Moment.js is a popular JavaScript library that simplifies working with date and time objects.

In this tutorial, we’ll explore how to use Moment.js to compute the difference between two calendar dates while excluding weekends.

Prerequisites

Before we get started, make sure you have Moment.js installed in your project. You can install it using npm:

npm install moment

Calculating the difference

To compute the difference between two dates using Moment.js, we’ll utilize the .diff() method. This method returns the difference in milliseconds between two moments.

const moment = require('moment');

// Define the start and end dates
const startDate = moment('2022-01-01');
const endDate = moment('2022-01-15');

// Compute the difference in milliseconds
const diffMilliseconds = endDate.diff(startDate);

console.log(diffMilliseconds);

The diffMilliseconds variable now holds the difference between the two dates in milliseconds.

Excluding weekends from the calculation

To exclude weekends from the calculation, we can utilize Moment.js’s .weekday() method. This method returns the day of the week, where Sunday is 0 and Saturday is 6.

const moment = require('moment');

// Define the start and end dates
const startDate = moment('2022-01-01');
const endDate = moment('2022-01-15');

let businessDays = 0;
let currentDate = startDate;

// Loop through each day
while (currentDate.isSameOrBefore(endDate)) {
  // Check if the current day is a weekend (Saturday or Sunday)
  if (currentDate.weekday() !== 0 && currentDate.weekday() !== 6) {
    businessDays++; // Increment the counter for business days
  }

  // Move to the next day
  currentDate = currentDate.add(1, 'day');
}

console.log(businessDays);

In the code above, we initialize a businessDays counter to keep track of the number of non-weekend days. We then loop through each day between the startDate and endDate. If the current day is not a Saturday or Sunday, we increment the businessDays counter. At the end of the loop, we have the total number of business days between the two dates.

Conclusion

With Moment.js, calculating the difference between two calendar dates excluding weekends becomes relatively straightforward. By utilizing Moment.js’s date manipulation capabilities, we can accurately compute the business days between two dates.

Make sure to explore Moment.js’s extensive documentation for more advanced date and time operations.