如何将mySql数据库连接到flutter应用程序？

// server.js
const express = require('express');
const mysql = require('mysql');

const app = express();
const port = 3000;

const connection = mysql.createConnection({
  host: 'localhost',
  user: 'your_username',
  password: 'your_password',
  database: 'your_database'
});

connection.connect((err) => {
  if (err) throw err;
  console.log('Connected to MySQL database!');
});

app.get('/users', (req, res) => {
  connection.query('SELECT * FROM users', (err, results) => {
    if (err) throw err;
    res.json(results);
  });
});

app.listen(port, () => {
  console.log(`Server running on port ${port}`);
});

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('MySQL Connection Example'),
        ),
        body: UsersList(),
      ),
    );
  }
}

class UsersList extends StatefulWidget {
  @override
  _UsersListState createState() => _UsersListState();
}

class _UsersListState extends State<UsersList> {
  List<dynamic> users = [];

  @override
  void initState() {
    super.initState();
    fetchUsers();
  }

  Future<void> fetchUsers() async {
    final response = await http.get(Uri.parse('http://localhost:3000/users'));
    if (response.statusCode == 200) {
      setState(() {
        users = jsonDecode(response.body);
      });
    } else {
      throw Exception('Failed to load users');
    }
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemCount: users.length,
      itemBuilder: (context, index) {
        return ListTile(
          title: Text(users[index]['name']),
          subtitle: Text(users[index]['email']),
        );
      },
    );
  }
}