Moment.js Parsing Validation

Date Validation in Moment.js moment#isValid is used to check whether a date is considered or not using Moment.js. This can be checked using moment#parsingFlags which returns an object in its response. Before proceeding, please install the moment.js library using the following command.

Moment.js moment#parsingFlags that results in an invalid date:

• overflow: It indicates a surge of a date field, for example, 30th February of the 13th Month.
• invalid month: It shows an invalid month name, such as January.
• empty: It means a string that is not parsable, for example, "this is a non-parsable string". 
• null input: It denotes a null input.
• invalid format: It denotes an empty list of formats passed to moment() 
• userInvalidated: It denotes a date explicitly created as invalid. 

Installation:

npm install moment

Syntax:

moment(date: String).isValid()

Parameters: moment().isValid() does not accept parameters.

Return value: It returns a boolean value that tells whether a date is valid or not. 

Example 1: In this example, we will create an invalid date and check with moment#isValid.

Filename: main.js

const moment = require('moment');
let m = moment("2022-10-10T10:20:90");
console.log(m.isValid()); 

Step to run the application: Open the terminal and type the following command.

node main.js

Output:

false

Example 2: In this example, we will create a valid date and check with moment#isValid.

Filename: main.js

const moment = require('moment');
let m = moment("2022-10-10T10:20:50");
console.log(m.isValid()); 

Step to run the application: Open the terminal and type the following command.

node main.js

Output:

true

Reference: https://momentjs.com/docs/#/parsing/is-valid/