Flutter网络发现插件 network_discovery 的使用

network_discovery 是一个用于在Dart/Flutter项目中进行网络设备发现的库。它可以帮助你通过ping IP子网来发现网络中的设备，并且可以检测特定端口上的服务（如HTTP服务器）。该库支持Android、iOS、Windows和Linux平台。

开始使用

安装

首先，在你的pubspec.yaml文件中添加依赖：

dependencies:
  network_discovery: ^1.0.0  # 使用最新版本号替换

然后运行flutter pub get来安装依赖。

示例代码

下面是一些常见的使用场景和示例代码，帮助你快速上手。

获取设备IP地址

import 'package:network_discovery/network_discovery.dart';

void main() async {
  // 必须是异步函数
  final String deviceIP = await NetworkDiscovery.discoverDeviceIpAddress();

  if (deviceIP.isNotEmpty) {
    print('设备IP地址: $deviceIP');
    // 可以用来获取子网信息
    final String subnet = deviceIP.substring(0, deviceIP.lastIndexOf('.'));
    print('子网: $subnet');
  } else {
    print("无法获取IP地址");
  }
}

发现指定地址和端口的服务

import 'package:network_discovery/network_discovery.dart';

void main() async {
  const port = 80;
  final device = await NetworkDiscovery.discoverFromAddress('192.168.0.1', port);

  print('发现设备: ${device.toString()}');
}

发现指定地址和多个端口的服务

import 'package:network_discovery/network_discovery.dart';

void main() async {
  const List<int> ports = [80, 443, 445, 8080];
  final device = await NetworkDiscovery.discoverFromAddressMultiplePorts('192.168.0.1', ports);

  print('发现设备: ${device.toString()}');
}

发现子网内的所有活动主机

import 'package:network_discovery/network_discovery.dart';

void main() {
  final stream = NetworkDiscovery.discoverAllPingableDevices('192.168.0');

  int availableHost = 0;
  stream.listen((HostActive host) {
    print('发现设备: ${host.ip}, 活动状态: ${host.isActive}');
    if (host.isActive) {
      availableHost++;
    }
  }).onDone(() => print('完成。可用的主机数量: $availableHost'));
}

发现子网内指定端口的活动设备

import 'package:network_discovery/network_discovery.dart';

void main() {
  const port = 80;
  final stream = NetworkDiscovery.discover('192.168.0', port);

  int found = 0;
  stream.listen((NetworkAddress addr) {
    found++;
    print('发现设备: ${addr.ip}:$port');
  }).onDone(() => print('完成。共找到 $found 设备'));
}

发现子网内多个端口的活动设备

import 'package:network_discovery/network_discovery.dart';

void main() {
  const List<int> ports = [80, 443, 445, 8080];
  final stream = NetworkDiscovery.discoverMultiplePorts('192.168.0', ports);

  int found = 0;
  stream.listen((NetworkAddress addr) {
    found++;
    print('发现设备: ${addr.ip}:${ports.join(", ")}');
  }).onDone(() => print('完成。共找到 $found 设备'));
}

完整示例Demo

为了更直观地展示如何使用这个插件，这里提供一个简单的Flutter应用示例：

import 'package:flutter/material.dart';
import 'package:network_discovery/network_discovery.dart';

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

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: '网络发现示例',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: '网络发现'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, required this.title}) : super(key: key);

  final String title;

  [@override](/user/override)
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  String _ipAddress = '';
  List<String> _devices = [];

  [@override](/user/override)
  void initState() {
    super.initState();
    _discoverDeviceIp();
    _discoverDevices();
  }

  Future<void> _discoverDeviceIp() async {
    final ip = await NetworkDiscovery.discoverDeviceIpAddress();
    setState(() {
      _ipAddress = ip;
    });
  }

  Future<void> _discoverDevices() async {
    final stream = NetworkDiscovery.discoverAllPingableDevices('192.168.0');
    stream.listen((HostActive host) {
      if (host.isActive) {
        setState(() {
          _devices.add(host.ip);
        });
      }
    }).onDone(() => print('发现完成'));
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('本机IP地址: $_ipAddress'),
            SizedBox(height: 20),
            Expanded(
              child: ListView.builder(
                itemCount: _devices.length,
                itemBuilder: (context, index) {
                  return ListTile(
                    title: Text(_devices[index]),
                  );
                },
              ),
            ),
          ],
        ),
      ),
    );
  }
}