Lodash _.indexOf() Method

lodash _.indexOf() method is used to get the index of the first occurrence of the particular element in the array. If fromIndex is not present in the array negative one is given as the output and no error is displayed.

Syntax:

indexOf(array, value, fromIndex);

Note:

If the value is not found in the array -1 is returned.

Parameters:

• array: It is the array in which value is to be found.
• value: It is the value to be looked at in the array.
• fromIndex: It is the index after which we have to look for the value.

Return Value:

It returns the index of the value in the array. If the value is not found, the array returns -1.

Example 1: In this example, we are getting the index at which the given value is present in the given array.

Javascript

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

// Original array
let array = [1, 2, 3, 4]

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

// Looking for value 3 from index 0
let index = _.indexOf(array, 3, 0)

// Printing the Index of the value
console.log("Index : ", index)

Output:

Example 2: In this example, we are getting -1 as the index becuase the given value is not present after the given index in the given array.

Javascript

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

// Original array
let array = [1, 2, 3, 4]

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

// Looking for 3 from index 3
// it will return -1
let index = _.indexOf(array, 3, 3)

// Print Index of the value
console.log("Index : ", index)

Output: