另一种方法，使用intl包。

创建DateTime的扩展:

date_time_extension.dart

import 'package:intl/date_symbol_data_local.dart';
import 'package:intl/intl.dart';

extension DateTimeExtension on DateTime {
  String format([String pattern = 'dd/MM/yyyy', String? locale]) {
    if (locale != null && locale.isNotEmpty) {
      initializeDateFormatting(locale);
    }
    return DateFormat(pattern, locale).format(this);
  }
}

导入你要使用DateTime类型的文件，你可以这样使用它:

DateTime.now().format();

DateTime.now().format('MM/yyyy');

DateTime.now().format('MM/yyyy', 'es');

可以使用intl包格式化flutter中的日期。

void main() {
  final DateTime now = DateTime.now();
  final DateFormat format = DateFormat('yyyy-MM-dd');
  final String formatted = format.format(now);
  // 2021-03-02
}

或者可以使用date_format包来格式化flutter中的日期。

import 'package:date_format/date_format.dart';

final formattedStr = formatDate(DateTime.now(), [dd, '-', mm, '-', yyyy]);

//02-03-2021

您还可以像前面所述的那样指定日期格式:https://pub.dev/documentation/intl/latest/intl/DateFormat-class.html

import 'package:intl/intl.dart';
String formatDate(DateTime date) => new DateFormat("MMMM d").format(date);

出品时间:3月4日

这就给你提供了社交网络中的日期:[“今天”，“昨天”，“星期的哪一天”，等等。]

void main() {
      DateTime now = new DateTime(2018,6,26);
      print(date(now));
    }
    
    String date(DateTime tm) {
      DateTime today = new DateTime.now();
      Duration oneDay = new Duration(days: 1);
      Duration twoDay = new Duration(days: 2);
      Duration oneWeek = new Duration(days: 7);
      String month;
      switch (tm.month) {
        case 1:
          month = "january";
          break;
        case 2:
          month = "february";
          break;
        case 3:
          month = "march";
          break;
        case 4:
          month = "april";
          break;
        case 5:
          month = "may";
          break;
        case 6:
          month = "june";
          break;
        case 7:
          month = "july";
          break;
        case 8:
          month = "august";
          break;
        case 9:
          month = "september";
          break;
        case 10:
          month = "october";
          break;
        case 11:
          month = "november";
          break;
        case 12:
          month = "december";
          break;
      }
    
      Duration difference = today.difference(tm);
    
      if (difference.compareTo(oneDay) < 1) {
        return "today";
      } else if (difference.compareTo(twoDay) < 1) {
        return "yesterday";
      } else if (difference.compareTo(oneWeek) < 1) {
        switch (tm.weekday) {
          case 1:
            return "monday";
          case 2:
            return "tuesday";
          case 3:
            return "wednesday";
          case 4:
            return "thursday";
          case 5:
            return "friday";
          case 6:
            return "saturday";
          case 7:
            return "sunday";
        }
      } else if (tm.year == today.year) {
        return '${tm.day} $month';
      } else {
        return '${tm.day} $month ${tm.year}';
      }
    }

如果你想将多个日期格式合并为一个，这就是我们使用intl的方法。

DateFormat('yMMMd').addPattern(DateFormat.HOUR24_MINUTE).format(yourDateTime))

 String dateConverter(String date) {
    // Input date Format
    final format = DateFormat("dd-MM-yyyy");
    DateTime gettingDate = format.parse(date);
    final DateFormat formatter = DateFormat('yyyy-MM-dd');
    // Output Date Format
    final String formatted = formatter.format(gettingDate);
    return date;
  }