Monday, December 22, 2025
HomeLanguagesJavascriptUnderscore.js _.isInstanceOf() Method

Underscore.js _.isInstanceOf() Method

The _.isInstanceOf() method checks whether the given value is the instance of a given constructor or not and returns the corresponding boolean value. 

Syntax:

_.isInstanceOf(value, constructor);

Parameters: 

  • value: Given value to be checked for instance.
  • constructor: Given constructor.

Return Value: This method returns a Boolean value(Returns true if the given value is instance, else false).

Note: This will not work in normal JavaScript because it requires the underscore.js contrib library to be installed. Underscore.js contrib library can be installed using npm install underscore-contrib .

Example 1:

Javascript




// Defining underscore contrib variable
var _ = require('underscore-contrib'); 
  
// Checking
console.log("The Value is Instance Of constructor : " 
    + _.isInstanceOf(new Date(),Date));


Output:

The Value is Instance Of constructor : true

Example 2:

Javascript




// Defining underscore contrib variable
var _ = require('underscore-contrib'); 
  
// Checking
console.log("The Value is Instance Of constructor : " 
    + _.isInstanceOf("abc",Date));


Output:

The Value is Instance Of constructor : false
Whether you’re preparing for your first job interview or aiming to upskill in this ever-evolving tech landscape, neveropen Courses are your key to success. We provide top-quality content at affordable prices, all geared towards accelerating your growth in a time-bound manner. Join the millions we’ve already empowered, and we’re here to do the same for you. Don’t miss out – check it out now!
RELATED ARTICLES

Most Popular

Dominic
32456 POSTS0 COMMENTS
Milvus
111 POSTS0 COMMENTS
Nango Kala
6823 POSTS0 COMMENTS
Nicole Veronica
11959 POSTS0 COMMENTS
Nokonwaba Nkukhwana
12038 POSTS0 COMMENTS
Shaida Kate Naidoo
6958 POSTS0 COMMENTS
Ted Musemwa
7203 POSTS0 COMMENTS
Thapelo Manthata
6911 POSTS0 COMMENTS
Umr Jansen
6890 POSTS0 COMMENTS