Lodash _.filter() Method

Lodash is a JavaScript library that works on the top of underscore.js. Lodash helps in working with arrays, collection, strings, objects, numbers etc.

The _.filter() method iterates over elements of collection, returning an array of all elements predicate returns true.

Note: This method is not similar to the _.remove() method as this method returns a new array.

Syntax:

_.filter( collection, predicate )

Parameters: This method accepts two parameters as mentioned above and described below:

• collection: This parameter holds the collection to iterate over.
• predicate: This parameter holds the function invoked per iteration.

Return Value: This method returns the new filtered array.

Example 1:

// Requiring the lodash library
const _ = require("lodash");

// Original array
var users = [
  { 'user': 'luv',
    'salary': 36000,
    'active': true },
  { 'user': 'kush',
    'salary': 40000,
    'active': false }
];

// Using the _.filter() method
let filtered_array = _.filter(
    users, function(o) {
       return !o.active;
    }
);

// Printing the output
console.log(filtered_array);

Output:

[ { user: 'kush', salary: 40000, active: false } ]

Example 2:

// Requiring the lodash library
const _ = require("lodash");

// Original array
var users = [
  { 'user': 'luv',
    'salary': 36000,
    'active': true },
  { 'user': 'kush',
    'salary': 40000,
    'active': false }
];

// Using the _.filter() method
// The `_.matches` iteratee shorthand
let filtered_array = _.filter(users,
    { 'salary': 36000, 'active': true }
);

// Printing the output
console.log(filtered_array);

Output:

[ { user: 'luv', salary: 36000, active: true } ]

Example 3:

// Requiring the lodash library
const _ = require("lodash");

// Original array
var users = [
  { 'user': 'luv',
    'salary': 36000,
    'active': true },
  { 'user': 'kush',
    'salary': 40000,
    'active': false }
];

// Using the _.filter() method
// The `_.matchesProperty` iteratee shorthand
let filtered_array =
  _.filter(users, ['active', false]);

// Printing the output
console.log(filtered_array);

Output:

[ { user: 'kush', salary: 40000, active: false } ]

Example 4:

// Requiring the lodash library
const _ = require("lodash");

// Original array
var users = [
  { 'user': 'luv',
    'salary': 36000,
    'active': true },
  { 'user': 'kush',
    'salary': 40000,
    'active': false }
];

// Using the _.filter() method
// The `_.property` iteratee shorthand
let filtered_array =
  _.filter(users, 'active');

// Printing the output
console.log(filtered_array);

Output:

[ { user: 'luv', salary: 36000, active: true } ]