date range filter in lodash for multiple day

Date Range Filter in Lodash for Multiple Days

If you are working on a project that requires filtering based on date ranges, Lodash can be a great tool to use. Lodash is a JavaScript utility library that provides many useful functions to make programming easier.

In this case, we are looking for a way to filter an array of objects that contain a date property, within a specific range of dates. Let's assume that the date property is stored as a string in the format "YYYY-MM-DD".

Using the _.filter() function

The easiest way to filter an array of objects based on a date range using Lodash is to use the _.filter() function. This function takes two arguments: the array to be filtered and a callback function that returns a boolean value indicating whether or not an item should be included in the filtered array.

To filter an array of objects with dates within a specific range, we can use the moment.js library. This library provides an easy way to parse and manipulate dates in JavaScript.

const startDate = moment('2021-06-01');
const endDate = moment('2021-06-30');

const filteredArray = _.filter(array, function(obj) {
  const date = moment(obj.date, 'YYYY-MM-DD');
  return date.isBetween(startDate, endDate, null, '[]');
});

In this example, we first create moment objects for the start and end dates of our range. We then use the _.filter() function to loop through our array of objects and return a new array with only the objects whose dates fall between our start and end dates.

The isBetween() function is used to check whether a given date is within a range. The first two arguments are the start and end dates of the range. The third argument is null because we don't want to use any specific units (like hours or minutes) to define the range. The fourth argument is a string that defines whether our range includes the start and end dates or not. In this case, we use [] to include both start and end dates in our range.

Using the _.partition() function

Another way to filter an array with Lodash is to use the _.partition() function. This function splits an array into two arrays based on a callback function. One array contains all the items that pass the callback test, while the other array contains all the items that fail the test.

const startDate = moment('2021-06-01');
const endDate = moment('2021-06-30');

const [filteredArray, excludedArray] = _.partition(array, function(obj) {
  const date = moment(obj.date, 'YYYY-MM-DD');
  return date.isBetween(startDate, endDate, null, '[]');
});

In this example, we are using the same start and end dates as before. We then pass our array and a callback function to the _.partition() function. The callback function tests if an object's date is within our range using the isBetween() function. The _.partition() function returns an array with two elements: the first containing all objects that passed the test, and the second containing all objects that failed.

Conclusion

In conclusion, Lodash provides many useful functions for working with arrays and objects in JavaScript. When it comes to filtering objects based on a date range, we can use the _.filter() or _.partition() functions along with the moment.js library to easily manipulate dates and check whether they fall within a specific range.