Lodash _.flatten() Method Last Updated : 02 Sep, 2024 Comments Improve Suggest changes Like Article Like Report 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: Comment More infoAdvertise with us Next Article Introduction to JavaScript T tarun007 Follow Improve Article Tags : JavaScript Web Technologies JavaScript-Lodash Lodash Array Similar Reads JavaScript Tutorial JavaScript is a programming language used to create dynamic content for websites. It is a lightweight, cross-platform, and single-threaded programming language. 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