如何在flutter中解析json

import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

class User {
  final int id;
  final String name;
  final String email;

  User({required this.id, required this.name, required this.email});

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

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  late Future<User> futureUser;

  @override
  void initState() {
    super.initState();
    futureUser = fetchUser();
  }

  Future<User> fetchUser() async {
    final response = await http.get(Uri.parse('https://example.com/api/user'));
    if (response.statusCode == 200) {
      return User.fromJson(jsonDecode(response.body));
    } else {
      throw Exception('Failed to load user');
    }
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('JSON Parsing Example'),
        ),
        body: Center(
          child: FutureBuilder<User>(
            future: futureUser,
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Text('ID: ${snapshot.data!.id}'),
                    Text('Name: ${snapshot.data!.name}'),
                    Text('Email: ${snapshot.data!.email}'),
                  ],
                );
              } else if (snapshot.hasError) {
                return Text('Error: ${snapshot.error}');
              }
              return CircularProgressIndicator();
            },
          ),
        ),
      ),
    );
  }
}

void main() {
  runApp(MyApp());
}