flutter pub add age_calculator根據套件公開資料產生的選型評估，僅供參考。
age_calculator 套件是一個專為 Flutter 設計的實用工具，用於計算一個人的年齡（以年、月、日表示）。它還允許使用者精確計算兩個日期之間的差異。適用於需要年齡驗證或日期比較的應用程式，例如健康應用、註冊表單或活動規劃工具。該套件支援所有主要平台，包括 Android、iOS、Web、macOS、Windows 和 Linux，確保跨平台的一致性。它為開發者提供了一個簡單直覺的 API，可輕鬆將年齡計算功能整合到其應用程式中。
以下為關聯原始碼儲存庫的 README 原文快照，最新內容請造訪原始碼儲存庫。
A Flutter package that allows you to perform operations between dates:
In your flutter project add the dependency:
dependencies: ... age_calculator: ^1.0.0
For help getting started with Flutter, view the online documentation.
import 'package:age_calculator/age_calculator.dart';
void main() {
DateTime birthday = DateTime(1997, 3, 5);
DateDuration duration;
// Find out your age as of today's date 2021-03-08
duration = AgeCalculator.age(birthday);
print('Your age is $duration'); // Your age is Years: 24, Months: 0, Days: 3
//Find out your age on any given date
duration = AgeCalculator.age(birthday, today: DateTime(2030, 5, 1));
print('Your age is $duration'); // Your age is Years: 33, Months: 1, Days: 26
// Find out when your next birthday will be at 2021-03-08
duration = AgeCalculator.timeToNextBirthday(birthday);
print('You next birthday will be in $duration');
// You next birthday will be in Years: 0, Months: 11, Days: 25
// Find out when your next birthday will be on any given date
duration = AgeCalculator.timeToNextBirthday(birthday,
fromDate: DateTime(2021, 3, 2));
print('You next birthday will be in $duration');
// You next birthday will be in Years: 0, Months: 0, Days: 3
// Find out the difference between two dates
duration = AgeCalculator.dateDifference(
fromDate: DateTime(2021, 1, 2),
toDate: DateTime(2025, 5, 2),
);
print('The difference is $duration');
// You next birthday will be in Years: 4, Months: 4, Days: 0
// Add time to any date
DateTime date = AgeCalculator.add(
date: DateTime(2021, 1, 2),
duration: DateDuration(years: 5, months: 2, days: 1));
print(date);
// 2026-03-03 00:00:00.000
}