date-formatter-js

A lightweight date and time formatter designed for log and console output. The formatting specifications are inspired by C# Custom Date and Time Format Strings.

Installation

npm install @ayapapa-npm/date-formatter-js

Interface

DateFormatter.format(date: Date = new Date(), pattern: string = "yyyy/MM/dd HH:mm:ss.fff");

Pattern specification element

| Token | Meaning | | ------ | ----------------------- | | yyyy | 4-digit year | | yy | 2-digit year | | MM | 2-digit month | | M | month | | dd | 2-digit day | | d | day | | HH | 2-digit hour (24-hour) | | H | hour (24-hour) | | mm | 2-digit minute | | m | minute | | ss | 2-digit second | | s | second | | fff | milliseconds (3 digits) | | ff | milliseconds (2 digits) | | f | milliseconds (1 digit) |

Usage

import { DateFormatter } from '@ayapapa-npm/date-formatter-js';

function outputDate(date: Date): void {
  const pattern: string = "yyyy/MM/dd HH:mm:ss.fff";
  const datetimeStr: string = DateFormatter.format(
    date,
    pattern
  );
  console.log('Datetime:', datetimeStr);
}

function main(): void {
  outputDate(new Date(2026, 7, 11, 12, 34, 56, 789)); // Datetime: "2026/08/11 12:34:56.789"
}