Published Aug 11, 2023
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The .setMilliseconds() method sets the milliseconds part of a Date object to the desired value. The .setMilliseconds() takes an integer argument ranging from 0 to 999, representing the new milliseconds value to be set. Only the milliseconds part of a date and time is modified.



Above code changes millisecond of dateObject to n, which is an integer between 1 and 999.

The return value of .setMilliseconds() is the new timestamp after updating milliseconds value of the original Date object in place. The .setMilliseconds() method returns the new timestamp value, which represents the number of milliseconds since January 1, 1970 00:00:00 UTC.


The code below sets the millisecond value of the given date to 421:

const eventDate = new Date('1/1/2023');
console.log('Original date:', eventDate);
console.log('Modified date:', eventDate);

This example results in the following output:

Original date: 2023-01-01T00:00:00.000Z
Modified date: 2023-01-01T00:00:00.421Z

Codebyte Example

The example below is runnable and demonstrates how to modify the millisecond value of a given date, eventDate, to be 112 milliseconds in the future.

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