BS-AD Date Converter

A versatile JavaScript/TypeScript package to convert dates between Bikram Sambat (BS) and Gregorian (AD) calendars, along with utilities for age calculation, date difference, and getting current dates. Supports dates in YYYY-MM-DD format.

Features

• Date Conversion: Convert AD to BS and BS to AD.
• TypeScript Support: Fully written in TypeScript with type definitions included.
• Date Utilities:
  • Calculate age in years, months, and days.
  • Find the difference between two dates.
  • Get the current date in both AD and BS formats.
• Validation: Robust validation for dates within the supported range.

Installation

npm install bs-ad-date-converter

Usage

Import

import { 
  bsToAd, 
  adToBs, 
  ageCalculater, 
  dateDifference, 
  getTodayDate 
} from 'bs-ad-date-converter';

Date Conversion

Convert BS to AD

const adDate = bsToAd('2078-01-01');
console.log(adDate); // Output: "2021-04-14"

Convert AD to BS

const bsDate = adToBs('2021-04-14');
console.log(bsDate); // Output: "2078-01-01"

Utilities

Get Current Date

Returns the current date in both AD and BS formats.

const { todayAdDate, todayBSDate } = getTodayDate();
console.log(`Today: ${todayBSDate} (BS) / ${todayAdDate} (AD)`);

Calculate Age

Calculate age from a birth date. You can specify the input date type ('AD' or 'BS').

// From AD DOB
const ageAD = ageCalculater('2000-01-01', 'AD');
console.log(ageAD); 
// Output: { years: 25, months: 0, days: 8 } (results vary based on current date)

// From BS DOB
const ageBS = ageCalculater('2056-09-17', 'BS');
console.log(ageBS);

Date Difference

Calculate the number of days between two dates. Both dates must be of the same type ('AD' or 'BS').

// Difference between two AD dates
const diffAD = dateDifference('2022-01-01', '2022-01-10', 'AD');
console.log(diffAD); // Output: 9

// Difference between two BS dates
const diffBS = dateDifference('2078-01-01', '2078-01-10', 'BS');
console.log(diffBS); // Output: 9

API Reference

bsToAd(bsDateStr: string): string

Converts a BS date string (YYYY-MM-DD) to AD. Throws an error if invalid.

adToBs(adDateStr: string): string

Converts an AD date string (YYYY-MM-DD) to BS. Throws an error if invalid or out of range.

getTodayDate(): { todayAdDate: string, todayBSDate: string }

Returns the current system date converted to both AD and BS strings.

ageCalculater(date: string, dateType: 'AD' | 'BS'): { years: number, months: number, days: number }

Calculates the age based on the provided date of birth. defaults dateType to 'AD'.

dateDifference(date1: string, date2: string, dateType: 'AD' | 'BS'): number

Calculates the absolute difference in days between date1 and date2. defaults dateType to 'AD'.

Supported Date Range

| Calendar | Start Date | End Date | | -------- | ---------- | ---------- | | BS | 1970-01-01 | 2099-12-30 | | AD | 1913-04-13 | 2043-04-13 |

Error Handling

Errors are thrown for invalid formats or dates outside the supported range.

try {
  bsToAd('2100-01-01');
} catch (e) {
  console.error(e.message); // "Invalid BS date" or range error
}

License

MIT © Nischal Dhakal

Author

• Nischal Dhakal - GitHub