这里我使用INTL包来建立两个模式，然后我创建一个函数来尝试解析每个模式的日期，如果失败，它会抛出一个异常

import 'package:intl/intl.dart';

void main() {
  // Parse Thu, 01 Jan 1970 00:00:00 +0000
  final formatter1 = DateFormat('E, dd MMM yyyy HH:mm:ss Z');
  final date1 = formatter1.parse('Thu, 01 Jan 1970 00:00:00 +0000');
  print(date1); // 1970-01-01 00:00:00.000Z
  
  // Parse Thu, 01 Jan 1970 00:00 GMT
  final formatter2 = DateFormat('E, dd MMM yyyy HH:mm zzz');
  final date2 = formatter2.parse('Thu, 01 Jan 1970 00:00 GMT');
  print(date2); // 1970-01-01 00:00:00.000Z
}

DateTime parseDate(String dateString) {
  final formatter1 = DateFormat('E, dd MMM yyyy HH:mm:ss Z');
  final formatter2 = DateFormat('E, dd MMM yyyy HH:mm zzz');
  
  try {
    return formatter1.parse(dateString);
  } catch (_) {}
  
  try {
    return formatter2.parse(dateString);
  } catch (_) {}
  
  throw Exception('Failed to parse date: $dateString');
}

您可以使用timezone将DateTime转换为TZDateTime

import 'package:timezone/timezone.dart' as tz;

...

DateTime dt = DateTime.now(); //Or whatever DateTime you want
final tzdatetime = tz.TZDateTime.from(dt, tz.local); //could be var instead of final