Category: Day.js

Day.js is a JavaScript library that lets us manipulate dates in our apps.

In this article, we’ll look at how to use Day.js to manipulate dates in our JavaScript apps.

Getting Seconds of a Date

We can get the value with the valueOf method or methods for getting the parts of the time.

To get the number of seconds in a Day.js date we can use the second method:

const dayjs = require("dayjs");  
const result = dayjs().second();  
console.log(result);

This is the same as the native getSeconds method.

Getting Minutes of a Date

To get the number of minutes in a Day.js date we can use the minute method:

const dayjs = require("dayjs");  
const result = dayjs().minute();  
console.log(result);

Getting Hours of a Date

To get the number of hours in a Day.js date we can use the hour method:

const dayjs = require("dayjs");  
const result = dayjs().hour();  
console.log(result);

Getting Month of a Date

To get the day of the month in a Day.js date we can use the date method:

const dayjs = require("dayjs");  
const result = dayjs().`date`();  
console.log(result);

Getting Day of the Week of a Date

To get the day of the week in a Day.js date we can use the day method:

const dayjs = require("dayjs");  
const result = dayjs().day();  
console.log(result);

Getting Locale-Aware Day of the Week of a Date

To get the locale-aware day of the week in a Day.js date we can use the weekday method:

const dayjs = require("dayjs");  
const result = dayjs().weekday();  
console.log(result);

Getting ISO Day of the Week of a Date

To get the ISO day of the week in a Day.js date we can use the isoWeekDay method available in the isoWeek plugin:

const dayjs = require("dayjs");  
const isoWeek = require("dayjs/plugin/isoWeek");  
dayjs.extend(isoWeek);  
const result = dayjs().isoWeekday();  
console.log(result);

We import the isoWeek plugin with:

const isoWeek = require("dayjs/plugin/isoWeek");

Conclusion

Day.js is a JavaScript library that lets us manipulate dates in our apps.

Day.js is a JavaScript library that lets us manipulate dates in our apps.

In this article, we’ll look at how to use Day.js to manipulate dates in our JavaScript apps.

Parsing Date to UTC Date

We can use the utc plugin to parse a date into a UTC date.

For instance, we can write:

const dayjs = require("dayjs");
const utc = require("dayjs/plugin/utc");

dayjs.extend(utc);
const dt = dayjs.utc().format();
console.log(dt);

to import the Day.js with the utc plugin.

Then we can use the plugin by writing:

dayjs.extend(utc);

Now we can call the dayjs.utc method to create a date object with the current date and time in UTC.

Clone a Date

We can clone a Day.js date object with the clone method.

For instance, we can write:

const dayjs = require("dayjs");
const a = dayjs();
const b = a.clone();
console.log(a, b);

We call dayjs to create date object a .

Then we call clone on a and assign it to b to make b a clone of a .

Validation

To validate a date, we can use the isValid method.

It returns true if the date is valid and false otherwise.

For instance, we can write:

const dayjs = require("dayjs");
const isValid = dayjs().isValid();
console.log(isValid);

We call isValid on a Day.js date object.

Since we called in a valid date, isValid is true .

Conclusion

Day.js is a JavaScript library that lets us manipulate dates in our apps.

Day.js is a JavaScript library that lets us manipulate dates in our apps.

In this article, we’ll look at how to use Day.js to manipulate dates in our JavaScript apps.

Parsing JavaScript Native Date Objects

We can pass in native JavaScript date objects as an argument of the dayjs function.

To do this, we write:

const d = new Date(2020, 8, 18)
const dt = dayjs(d)
console.log(dt)

Parsing Plain JavaScript Objects into Dates

To parse plain JavaScript objects into dates, we can use the objectSupport plugin.

For instance, we can write:

const dayjs = require("dayjs");
const objectSupport = require("dayjs/plugin/objectSupport");

dayjs.extend(objectSupport);
const dt = dayjs({
  year: 2020,
  month: 3,
  day: 5,
  hour: 15,
  minute: 10,
  second: 3,
  millisecond: 123
});
console.log(dt);

We import the dayjs and dayjs/plugin/objectSupport modules to add the day.js library with the objectSupport plugin.

Then we add:

dayjs.extend(objectSupport);

to add the objectSupport plugin.

Now we can pass in an object into the dayjs function to parse it into a date.

Parsing JavaScript Array into Dates

Day.js also comes with the ArraySupport plugin that lets us parse an array of numbers into dates.

For instance, we can write:

const dayjs = require("dayjs");
const arraySupport = require("dayjs/plugin/arraySupport");

dayjs.extend(arraySupport);
const dt = dayjs([2020, 1, 14, 15, 25, 50, 125]);
console.log(dt);

to import the Day.js and arraySupport library respectively in the first 2 lines.

Then we add:

dayjs.extend(arraySupport);

to add the arraySupport plugin.

Now we can pass in an array into the dayjs function to parse the array into a date.

The order of the numbers in the array is year, month, day of the month, hour, minutes, seconds, and milliseconds.

Conclusion

Day.js is a JavaScript library that lets us manipulate dates in our apps.

Day.js is a JavaScript library that lets us manipulate dates in our apps.

In this article, we’ll look at how to use Day.js to manipulate dates in our JavaScript apps.

Installation

We can install Day.js for Node.js or TypeScript apps by running:

npm install dayjs

If we use it in our TypeScript project, then we must add the following to compiler options to tsconfig.json :

{  
  "compilerOptions": {  
    "esModuleInterop": true,  
    "allowSyntheticDefaultImports": true,  
  }  
}

If we want to use it in the browser, we can add the script tag version of it with:

<script src="https://unpkg.com/dayjs@1.8.21/dayjs.min.js"></script>

Parsing Dates

We can create a Day.js date object with the dayjs function:

const now = dayjs()  
console.log(now)

This creates a Day.js date object with the current date and time.

We can also pass in a date string into the dayjs function:

const dt = dayjs('2020-04-04T16:00:00.000Z')  
console.log(dt)

And dt is a Day.js object with the given date.

We can also specify the date string’s format when we’re parsing it:

const dt = dayjs('05/02/20 1:02:03 PM -05:00', 'MM/DD/YY H:mm:ss A Z')  
console.log(dt)

Timestamps can also be parsed into a Day.js date object:

const dt = dayjs(1318781876406)  
console.log(dt)

To parse a date from the timestamp converted to a number of seconds, we can use the unix method:

const dt = dayjs.unix(1318781876.721)  
console.log(dt)

Conclusion

Day.js is a JavaScript library that lets us manipulate dates in our apps.