The Lodash _.exists() method checks whether the given value is Exist or not and returns the corresponding boolean value. Both null and undefined are considered non-existy values. All other values are “Existy”.
Syntax:
_.exists( value );
Parameters: This method accepts single parameter as mentioned above and described below:
- value: Given value to be checked for Existy value.
Return Value: This method returns a Boolean value true if the given value is Existy, else false.
Note: This will not work in normal JavaScript because it requires the lidash.js contrib library to be installed. Lodash.js contrib library can be installed using npm install lodash-contrib.
Example 1:
Javascript
// Defining underscore lodash variable var _ = require('lodash-contrib'); var bool = _.exists("Geeks"); console.log("Check the Existenc of Given Value : ", bool); |
Output:
Check the Existenc of Given Value : true
Example 2:
Javascript
// Defining underscore lodash variable var _ = require('lodash-contrib'); var bool = _.exists(undefined); console.log("Check the Existenc of Given Value : ", bool); |
Output:
Check the Existenc of Given Value : false
Example 3:
Javascript
// Defining underscore lodash variable var _ = require('lodash-contrib'); var bool = _.exists(null); console.log("Check the Existenc of Given Value : ", bool); |
Output:
Check the Existenc of Given Value : false
Example 4:
Javascript
// Defining underscore lodash variable var _ = require('lodash-contrib'); var bool = _.exists([1, 12, 2, 3]); console.log("Check the Existenc of Given Value : ", bool); |
Output:
Check the Existenc of Given Value : true
