Lodash _.forIn() Method

Namachila October 31, 2025

0 2 1 minute read

The Lodash _.forIn() Method Iterates over keys and values of the given object and invokes iteratee function for each property. The iteratee is invoked with three arguments: (value, key, object). Iteratee functions may exit iteration early by explicitly returning false.

Syntax:

_.forIn( object, iteratee_function)

Parameters: This method accepts two parameters as mentioned above and described below:

object: This is the object to find in.
iteratee_function: the function that is invoked per iteration.

Return Value: This method returns an object.

Example 1:

// Defining Lodash variable  
const _ = require('lodash');  
  
var users = { 
  'a':  1, 
  'b':  2, 
  'c':  3 
}; 
   
_.forIn(users, function(value, key) { 
  console.log(key); 
});

Output:

a
b
c

Example 2:

// Defining Lodash variable  
const _ = require('lodash');  
  
var users = { 
  'a':  1, 
  'b':  2, 
  'c':  3 
}; 
   
_.forIn(users, function(value, key) { 
    if(value > 1) { 
        console.log(key, value); 
    } 
});

Output:

b 2
c 3

Note: This will not work in normal JavaScript because it requires the lodash library to be installed and can be installed using the following command: