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 absent in the array, a 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.

// 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.

// 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: