Lodash _.flatten() Method

Lodash _.flatten() method is used to flatten the array to one level deep and it returns a new flattened array.

Syntax:

_.flatten( array );

Parameter:

• array that holds a simple array or array of arrays.

Return Value:

The return type of this function is an array.

Example 1: In this example, er are flattening the array to a single level by the use of the _.flatten() method.

Javascript

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

// Original array
let array1 = [[1, 2], [4, 5], [7, 8]]

// Using _.flatten() method
let newArray = _.flatten(array1);

// Printing original Array
console.log("original Array1: ", array1)

// Printing the newArray
console.log("new Array: ", newArray)

Output:

Example 2: In this example, er are flattening the array of object to a single level by the use of the _.flatten() method.

Javascript

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

// Original array
let array1 = [[{ "a": 1 }],
[{ "b": 2 }, { "c": 3 }]]

// Using _.flatten() method
let newArray = _.flatten(array1);

// Printing original Array
console.log("original Array1: ", array1)

// Printing the newArray
console.log("new Array: ", newArray)

Output:

Example 3: In this example, er are flattening the empty array to a single level by the use of the _.flatten() method.

Javascript

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

// Original array
let array1 = [[], [[[]]], [[]], []]

// Using _.flatten() method
let newArray = _.flatten(array1);

// Printing original Array
console.log("original Array1: ", array1)

// Printing the newArray
console.log("new Array: ", newArray)

Output: