What is the JavaScript date object?

The date object is used to handle dates and time in JavaScript.

The object can be instantiated in four ways:

let date = new Date()
let date = new Date(milliseconds)  
let date = new Date(dateString)  
let date = new Date(year, month, day, hrs, min, sec, milliseconds) 

Constructors

• new Date(): Creates a date object set to the current date and time.
• new Date(milliseconds): Takes an integer as an argument - which represents milliseconds - and sets the date object to the given number of milliseconds after 1/1/1970. For example, new date(7000) would set the object to 7 seconds after 1/1/1970.
• new Date(dateString): Takes a string representation of a date, in a format accepted by the date.parse() method, as an argument.
• new Date(year, month, day, hours, minutes, seconds, milliseconds): Takes arguments in the given order, each specifying a part of the date.

Examples

Date Methods

Once a date object is instantiated, there are several methods that can be used with it. Some are get methods - which enable you to retrieve specific information from a date, while orders are set methods, which let you edit the information in a date object.

Let’s see some of the important ones in action:

1. getDay(): Returns an integer which represents the day - 0 means Monday, 1 means Tuesday and so on.

2. getFullYear(): Returns an integer that represents the year in the date object.

3. getHours(): Returns an integer that represents the hours in the date object.

4. getMinutes(): Returns an integer representing minutes in the date object.

5. setFullYear(value): Sets the current year in the date to value.

Note: Do not use the deprecated setYear() anymore.

6. setMonth(value): Takes an integer as an argument which represents the month and changes the month in the date object to value.

Other methods such as setDay(value), setHours(value), setMinutes(value), and setSeconds(value) are used similarly.

Note: Numbering for setMonth() and setDay() starts from 0, so 0 means January, 1 means February and so on…