如何在flutter中解析复杂的Json值？

class Person {
  String name;
  int age;

  Person({this.name, this.age});

  factory Person.fromJson(Map<String, dynamic> json) {
    return Person(
      name: json['name'],
      age: json['age'],
    );
  }
}

import 'package:http/http.dart' as http;

Future<Person> fetchPerson() async {
  final response = await http.get('https://example.com/api/person');

  if (response.statusCode == 200) {
    final jsonMap = json.decode(response.body);
    return Person.fromJson(jsonMap);
  } else {
    throw Exception('Failed to fetch person');
  }
}

class Person {
  String name;
  int age;

  Person({this.name, this.age});

  factory Person.fromJson(Map<String, dynamic> json) {
    return Person(
      name: json['name'],
      age: json['age'],
    );
  }
}

import 'package:http/http.dart' as http;

Future<Person> fetchPerson() async {
  final response = await http.get('https://example.com/api/person');

  if (response.statusCode == 200) {
    final jsonMap = json.decode(response.body);
    return Person.fromJson(jsonMap);
  } else {
    throw Exception('Failed to fetch person');
  }
}

@override
Widget build(BuildContext context) {
  return FutureBuilder<Person>(
    future: fetchPerson(),
    builder: (context, snapshot) {
      if (snapshot.hasData) {
        final person = snapshot.data;
        return Text('Name: ${person.name}, Age: ${person.age}');
      } else if (snapshot.hasError) {
        return Text('Error: ${snapshot.error}');
      } else {
        return CircularProgressIndicator();
      }
    },
  );
}