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 _.reject() method is opposite of _.filter() method and this method returns elements of the collection that predicate does not return true.
Syntax:
_.reject(collection, predicate)
Parameters: This method accepts two parameters as mentioned above and described below:
- collection: This parameter holds the collection to iterate over.
- iteratee: This parameter holds the function invoked per iteration.
Return Value: This method is used to return the new filtered array.
Example 1: Here, const _ = require(‘lodash’) is used to import the lodash library in the file.
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var users = [ { 'user' : 'Rohit' , 'age' : 25, 'active' : false }, { 'user' : 'Mohit' , 'age' : 26, 'active' : true } ]; // Use of _.reject() method let gfg = _.reject(users, function (o) { return !o.active; }); // Printing the output console.log(gfg); |
Output:
[ { user: 'Mohit', age: 26, active: true } ]
Example 2:
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var users = [ { 'employee' : 'Rohit' , 'salary' : 50000, 'active' : false }, { 'employee' : 'Mohit' , 'salary' : 55000, 'active' : true } ]; // Use of _.reject() method // The `_.matches` iteratee shorthand let gfg = _.reject(users, { 'salary' : 55000, 'active' : true }); // Printing the output console.log(gfg); |
Output:
[ { employee: Rohit, salary: 50000, active: false } ]
Example 3:
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var users = [ { 'employee' : 'Rohit' , 'salary' : 50000, 'active' : false }, { 'employee' : 'Mohit' , 'salary' : 55000, 'active' : true } ]; // Use of _.reject() method // The `_.matchesProperty` iteratee shorthand let gfg = _.reject(users, [ 'active' , false ]); // Printing the output console.log(gfg); |
Output:
[ { employee: Mohit, salary: 55000, active: true } ]
Example 4:
javascript
// Requiring the lodash library const _ = require( "lodash" ); // Original array var users = [ { 'employee' : 'Rohit' , 'salary' : 50000, 'active' : false }, { 'employee' : 'Mohit' , 'salary' : 55000, 'active' : true } ]; // Use of _.reject() method // The `_.property` iteratee shorthand let gfg = _.reject(users, 'active' ); // Printing the output console.log(gfg); |
Output:
[ { employee: Rohit, salary: 50000, active: false } ]
Note: This code will not work in normal JavaScript because it requires the library lodash to be installed.