Lodash _.iteratee() Method

Lodash_.iteratee method  creates a function that invokes func with the arguments of the created function. If func is a property name, the created function returns the property value for a given element. If func is an array or object, the created function returns true for elements that contain the equivalent source properties, otherwise it returns false.

Syntax:

_.iteratee([func=_.identity])

Parameters:

This method accepts one parameter as mentioned above and described below:

• [func=_.identity]: The value to convert to a callback.

Returns:

[Function] Returns the callback.

Example 1: In this example, the the code uses the Lodash library to filter an array of objects based on a specific property value using the _.filter() method and a custom _.iteratee() function.

javascript

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

// Use of _.iteratee() method
let info = [
  { 'company': 'Geeksforgeeks', 'Location': 'Noida', 'active': true },
  { 'company': 'Google',   'Location': 'California', 'active': true }
];

let gfg = _.filter(info, _.iteratee({ 'Location': 'Noida' }));

// Printing the output
console.log(gfg)

Note: Here, const _ = require(‘lodash’) is used to import the lodash library in the file.

Output:

[Object {Location: "Noida", active: true, company: "Geeksforgeeks"}]

Example 2: In this example, the code uses the Lodash library to transform an array of objects by extracting property values using a custom _.iteratee() function and the _.map() method.

javascript

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

// Use of _.iteratee() method
let user = [
  { 'name': 'XXXX', 'age': 36, 'active': true },
  { 'name': 'YYYY',   'age': 40, 'active': false },
  { 'name': 'ZZZZ',   'age': 40, 'active': true }
];

let gfg = _.map(user, _.iteratee('name'));

// Printing the output
console.log(gfg)

Note: Here, const _ = require(‘lodash’) is used to import the lodash library in the file.

Output:

["XXXX", "YYYY", "ZZZZ"]