/// Get date as a string for display.
String getFormattedDate(String date) {
  /// Convert into local date format.
  var localDate = DateTime.parse(date).toLocal();

  /// inputFormat - format getting from api or other func.
  /// e.g If 2021-05-27 9:34:12.781341 then format must be yyyy-MM-dd HH:mm
  /// If 27/05/2021 9:34:12.781341 then format must be dd/MM/yyyy HH:mm
  var inputFormat = DateFormat('yyyy-MM-dd HH:mm');
  var inputDate = inputFormat.parse(localDate.toString());

  /// outputFormat - convert into format you want to show.
  var outputFormat = DateFormat('dd/MM/yyyy HH:mm');
  var outputDate = outputFormat.format(inputDate);

  return outputDate.toString();
} 

如果不想添加另一个库，也可以使用此方法

  DateTime dateTime = DateTime.now();
  String YYYY_MM_DD = dateTime.toIso8601String().split('T').first;
  print(YYYY_MM_DD); //2020-11-23

目前天:

DateTime.now().day, //something like 26

目前月:

DateTime.now().month, //something like 4

本年度:

DateTime.now().year, //something like 2022

目前Houre:

DateTime.now().hour, //something like 12

当前时间:

DateTime.now().minute, //something like 13

目前第二:

DateTime.now().second, //something like 44

pubspec.yaml:

dependencies:
  intl:

main.dart:

import 'package:intl/intl.dart'; // for date format
import 'package:intl/date_symbol_data_local.dart'; // for other locales

void main() {
  var now = DateTime.now();
  print(DateFormat().format(now)); // This will return date using the default locale
  print(DateFormat('yyyy-MM-dd hh:mm:ss').format(now));
  print(DateFormat.yMMMMd().format(now)); // print long date 
  print(DateFormat.yMd().format(now)); // print short date 
  print(DateFormat.jms().format(now)); // print time 

  initializeDateFormatting('es'); // This will initialize Spanish locale
  print(DateFormat.yMMMMd('es').format(now)); // print long date in Spanish format
  print(DateFormat.yMd('es').format(now)); // print short date in Spanish format
  print(DateFormat.jms('es').format(now)); // print time in Spanish format
}

结果:

May 31, 2020 5:41:42 PM
2020-05-31 05:41:42
May 31, 2020
5/31/2020
5:41:42 PM
31 de mayo de 2020
31/5/2020
17:41:42

String formatDate(String date) {
    return date.substring(0, 10).split('-').reversed.join().replaceAll('-', '/');
    
  }

From format "yyyy-mm-dd H:i:s"

由于flutter常用的Datetime库不知道德国的区域设置——de、de、de_DE、de- de或任何其他组合都不知道，例如，如果您希望用人类可读的字符串编写月份名称或日期名称，我建议您使用以下代码。

安装pub flutter pub add date_format

String formattedDate = formatDate(DateTime(year, month, day),[dd,'. ', MM, ' ', yyyy], locale: GermanDateLocale());