MAUI 初体验 联合 WinForm 让家里废弃的手机当做电脑副品用起来

软件效果图

软件架构草图

效果解释：运行 winform 端后 使用 ctrl+c 先复制任何词语，然后ctrl+空格 就可以将翻译结果显示在 安卓，IOS，windows 甚至 mac 任意客户端

1：使用 VS2022 + net6 创建 MAUI 项目，创建不了的先安装

2：创建时使用 .NET MAUI 应用，应用名字自己定义，我这里用 MauiAppClient

3：创建后的项目图

4：添加项目引用

CommunityToolkit.Mvvm MAUI 的官方 MVVM 库，可以很方便的让C#像VUE那样简单的使用双向绑定
MQTTnet 这里我们 MAUI 客户端和服务端之间使用 MQTT 协议来通信
Newtonsoft.Json 这个不解释，不引用也可以直接使用官方的 System.Text.Json

5:打开 MainPage.xaml 将文件修改为一下内容，MainPage.xaml内容为APP软件主程序窗口页面内容

`<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="MauiAppClient.MainPage"
             xmlns:viewmodel="clr-namespace:MauiAppClient.ViewModel"
             x:DataType="viewmodel:MainPageModel"
             BackgroundColor="Black"
             >

    <ScrollView>
        <StackLayout Margin="20,35,20,25">

            <Label
                    x:Name="LabelTips"
                    Text="{Binding StrTips}"
                    FontSize="12"
                    TextColor="Red"
                    Margin="15"
                    />

            <Label
                    x:Name="LabelKey"
                    Text="{Binding StrKey}"
                    FontSize="32"
                    TextColor="GreenYellow"
                    Margin="15"
                    />

            <Label
                    x:Name="LabelValue1"
                    Text="{Binding StrValue1}"
                    FontSize="26"
                    TextColor="#08e589"
                    Margin="15"
                    />

            <Label
                    x:Name="LabelValue2"
                    Text="{Binding StrValue2}"
                    FontSize="26"
                    TextColor="#08e589"
                    Margin="15"
                    />
        </StackLayout>
    </ScrollView>

</ContentPage>
`

6：创建页面绑定视图模型 有不熟悉 CommunityToolkit.Mvvm 组件的同学建议先查阅下此组件的使用方式。加好模型后记得注入一下 builder.Services.AddSingleton();

    public partial class MainPageModel : ObservableObject
    {
        [ObservableProperty]
        public string strTips;

        [ObservableProperty]
        public string strKey;

        [ObservableProperty]
        public string strValue1;

        [ObservableProperty]
        public string strValue2;
    }

7：MAUI 程序主代码

        public static IMqttClient _mqttClient;
        public MainPageModel _vm;
        public MainPage(MainPageModel vm)
        {
            InitializeComponent();
            _vm = vm;
            BindingContext = _vm;
            MqttInit();
        }

        /// <summary>
        /// 初始化MQTT
        /// </summary>
        public void MqttInit()
        {
            string clientId = Guid.NewGuid().ToString();
            var optionsBuilder = new MqttClientOptionsBuilder()
                .WithTcpServer("xxx.xxx.xxx.xxx", 1883) // 要访问的mqtt服务端的 ip 和 端口号
                                                        //.WithCredentials("admin", "123456") // 要访问的mqtt服务端的用户名和密码
                .WithClientId(clientId) // 设置客户端id
                .WithCleanSession()
                .WithTls(new MqttClientOptionsBuilderTlsParameters
                {
                    UseTls = false  // 是否使用 tls加密
                });

            var clientOptions = optionsBuilder.Build();
            _mqttClient = new MqttFactory().CreateMqttClient();
            _mqttClient.ConnectedAsync += _mqttClient_ConnectedAsync; // 客户端连接成功事件
            _mqttClient.DisconnectedAsync += _mqttClient_DisconnectedAsync; // 客户端连接关闭事件
            _mqttClient.ApplicationMessageReceivedAsync += _mqttClient_ApplicationMessageReceivedAsync; // 收到消息事件
            _mqttClient.ConnectAsync(clientOptions);
        }

        /// <summary>
        /// 客户端连接关闭事件
        /// </summary>
        /// <param name="arg"></param>
        /// <returns></returns>
        private Task _mqttClient_DisconnectedAsync(MqttClientDisconnectedEventArgs arg)
        {
            _vm.StrTips = "已断开与服务端的连接";
            int i = 0;
            Task.Factory.StartNew(() =>
            {
                while (_mqttClient == null || _mqttClient.IsConnected == false)
                {
                    i++;
                    Thread.Sleep(5 * 1000);
                    MqttInit();
                    _mqttClient.SubscribeAsync("pc-helper", MqttQualityOfServiceLevel.AtLeastOnce);
                    _vm.StrTips = "尝试重新连..." + i;
                }
            }).ConfigureAwait(false);

            return Task.CompletedTask;
        }

        /// <summary>
        /// 客户端连接成功事件
        /// </summary>
        /// <param name="arg"></param>
        /// <returns></returns>
        private Task _mqttClient_ConnectedAsync(MqttClientConnectedEventArgs arg)
        {
            _vm.StrTips = "已连接服务端";
            _mqttClient.SubscribeAsync("pc-helper", MqttQualityOfServiceLevel.AtLeastOnce);

            return Task.CompletedTask;
        }
        /// <summary>
        /// 收到消息事件
        /// </summary>
        /// <param name="arg"></param>
        /// <returns></returns>
        private Task _mqttClient_ApplicationMessageReceivedAsync(MqttApplicationMessageReceivedEventArgs arg)
        {
            string msg = Encoding.UTF8.GetString(arg.ApplicationMessage.Payload);
            var model = Newtonsoft.Json.JsonConvert.DeserializeObject<MsgModel>(msg);
            _vm.StrKey = "词语：" + model.query?.ToString();

            string value1 = "翻译：";
            if (model.translation != null)
            {
                foreach (var item in model.translation)
                {
                    value1 += item;
                }
            }
            _vm.StrValue1 = value1;

            string value2 = "解释：";
            if (model.basic != null && model.basic.explains != null)
            {
                foreach (var item in model.basic.explains)
                {
                    value2 += item;
                }
            }

            _vm.StrValue2 = value2;
            return Task.CompletedTask;
        }

        public void Publish(string data)
        {
            var message = new MqttApplicationMessage
            {
                Topic = "pc-helper",
                Payload = Encoding.Default.GetBytes(data),
                QualityOfServiceLevel = MqttQualityOfServiceLevel.AtLeastOnce,
                Retain = true  // 服务端是否保留消息。true为保留，如果有新的订阅者连接，就会立马收到该消息。
            };
            _mqttClient.PublishAsync(message);
        }

MAUI 发布 APK 供手机下载安装使用 右键 MAUI 项目>使用终端 输入如下命令

keytool -genkey -v -keystore myapp.keystore -alias key -keyalg RSA -keysize 2048 -validity 10000

项目文件中增加如下配置

<PropertyGroup Condition="$(TargetFramework.Contains('-android')) and '$(Configuration)' == 'Release'">
    <AndroidKeyStore>True</AndroidKeyStore>
    <AndroidSigningKeyStore>myapp.keystore</AndroidSigningKeyStore>
    <AndroidSigningKeyAlias>key</AndroidSigningKeyAlias>
    <AndroidSigningKeyPass></AndroidSigningKeyPass>
    <AndroidSigningStorePass></AndroidSigningStorePass>
</PropertyGroup>

发布

dotnet publish -f:net6.0-android -c:Release /p:AndroidSigningKeyPass=youpwd /p:AndroidSigningStorePass=youpwd 替换命令中的 youpwd

参考官方 发布 文章 https://learn.microsoft.com/zh-cn/dotnet/maui/android/deployment/publish-cli

8：创建 winform 程序 使用 .net framework 4.7 主要使用全局快捷方式 需要用到 user32.dll 主程序代码

 public partial class MainForm : Form
    {
        int crtlSpace;//定义快捷键
        public static IMqttClient _mqttClient;
        public MainForm()
        {
            InitializeComponent();
            crtlSpace = "CtrlSpace".GetHashCode();

            //组合键模式 None = 0,Alt = 1,Ctrl = 2,Shift = 4,WindowsKey = 8
            Win32Api.RegisterHotKey(this.Handle, crtlSpace, 2, (int)Keys.Space);
        }

        /// <summary>
        /// 热键
        /// </summary>
        /// <param name="m"></param>
        protected override void WndProc(ref Message m)
        {
            const int WM_HOTKEY = 0x0312;
            int wParam = (int)m.WParam;
            switch (m.Msg)
            {
                case WM_HOTKEY:
                    if (wParam == crtlSpace)
                    {
                        var text = Clipboard.GetText();
                        string result= YouDao.GetFanYiResult(text);
                        Publish(result);
                        AppentTextLog("触发:【" + text + "】->" + System.DateTime.Now);
                    }
                    break;
            }
            base.WndProc(ref m);
        }

        /// <summary>
        /// 隐藏窗体
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button_closed_Click(object sender, EventArgs e)
        {
            this.Visible = false;
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            MqttInit();
        }

        /// <summary>
        /// 窗口拖拽
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void MainForm_MouseDown(object sender, MouseEventArgs e)
        {
            Win32Api.ReleaseCapture();
            Win32Api.SendMessage(this.Handle, Win32Api.WM_SYSCOMMAND, Win32Api.SC_MOVE + Win32Api.HTCAPTION, 0);
        }

        /// <summary>
        /// 双击右下角图标显示隐藏
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void notifyIcon1_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                this.Visible = !this.Visible;
            }
        }

        /// <summary>
        /// 右键右下角图标退出程序
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void 退出ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //卸载注册热键
            Win32Api.UnregisterHotKey(this.Handle, this.crtlSpace);
            //关闭窗口
            this.Close();
        }

        /// <summary>
        /// 初始化MQTT
        /// </summary>
        public void MqttInit()
        {
            string clientId=Guid.NewGuid().ToString();
            var optionsBuilder = new MqttClientOptionsBuilder()
                .WithTcpServer("xxx.xxx.xxx.xxx", 1883) // 要访问的mqtt服务端的 ip 和 端口号
                                                        //.WithCredentials("admin", "123456") // 要访问的mqtt服务端的用户名和密码
                .WithClientId(clientId) // 设置客户端id
                .WithCleanSession()
                .WithTls(new MqttClientOptionsBuilderTlsParameters
                {
                    UseTls = false  // 是否使用 tls加密
                });

            var clientOptions = optionsBuilder.Build();
            _mqttClient = new MqttFactory().CreateMqttClient();
            _mqttClient.ConnectedAsync += _mqttClient_ConnectedAsync; // 客户端连接成功事件
            _mqttClient.DisconnectedAsync += _mqttClient_DisconnectedAsync; // 客户端连接关闭事件
            _mqttClient.ConnectAsync(clientOptions);
        }

        /// <summary>
        /// 客户端连接关闭事件
        /// </summary>
        /// <param name="arg"></param>
        /// <returns></returns>
        private Task _mqttClient_DisconnectedAsync(MqttClientDisconnectedEventArgs arg)
        {
            AppentTextLog($"MQTT服务已关闭");
            return Task.CompletedTask;
        }

        /// <summary>
        /// 客户端连接成功事件
        /// </summary>
        /// <param name="arg"></param>
        /// <returns></returns>
        private Task _mqttClient_ConnectedAsync(MqttClientConnectedEventArgs arg)
        {
            AppentTextLog($"MQTT服务已连接^v^");

            _mqttClient.SubscribeAsync("pc-helper", MqttQualityOfServiceLevel.AtLeastOnce);

            return Task.CompletedTask;
        }

        /// <summary>
        /// 发送MQTT消息
        /// </summary>
        /// <param name="data"></param>
        public void Publish(string data)
        {
            var message = new MqttApplicationMessage
            {
                Topic = "pc-helper",
                Payload = Encoding.UTF8.GetBytes(data),
                QualityOfServiceLevel = MqttQualityOfServiceLevel.AtLeastOnce,
                Retain = true  // 服务端是否保留消息。true为保留，如果有新的订阅者连接，就会立马收到该消息。
            };
            _mqttClient.PublishAsync(message);
        }

        /// <summary>
        /// 更新窗体文本
        /// </summary>
        /// <param name="text"></param>
        void AppentTextLog(string text)
        {
            Action act = delegate ()
            {
                textBox_log.AppendText(Environment.NewLine + text + Environment.NewLine);
                textBox_log.ScrollToCaret();

                if (textBox_log.Text.Count() > 100000)
                {
                    textBox_log.Clear();
                }
            };
            this.Invoke(act);
        }
    }

9:翻译API这里使用了“有道”

        public static string GetFanYiResult(string text)
        {
            Dictionary<String, String> dic = new Dictionary<String, String>();
            string url = "https://openapi.youdao.com/api";
            string appKey = "xxx";
            string appSecret = "xxx";
            string salt = Guid.NewGuid().ToString();
            dic.Add("from", "auto");
            dic.Add("to", "zh-CHS");
            dic.Add("signType", "v3");
            TimeSpan ts = (DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc));
            long millis = (long)ts.TotalMilliseconds;
            string curtime = Convert.ToString(millis / 1000);
            dic.Add("curtime", curtime);
            string signStr = appKey + Truncate(text) + salt + curtime + appSecret;
            string sign = ComputeHash(signStr, new SHA256CryptoServiceProvider());
            dic.Add("q", text);
            dic.Add("appKey", appKey);
            dic.Add("salt", salt);
            dic.Add("sign", sign);
            return Post(url, dic);
        }

10: 到这里两个端都有了，就差最关键的 MQTT 服务了。MQTTnet 组件本身是可以起身起一个服务供软件使用的（有兴趣的同学可以自己扩展），这里我们直接使用 docker 线上部署一个 mqtt 服务 (emqx,感兴趣的同学可以查阅此工具，自带web管理)

docker run -dit --restart=always -d --name emqx -e EMQX_HOST="127.0.0.1" -e EMQX_NAME="emqx"  -p 4369:4369 -p 4370:4370 -p 5369:5369 -p 8083:8083 -p 8084:8084 -p 8883:8883 -p 0.0.0.0:1883:1883 -p 0.0.0.0:18083:18083 -p 0.0.0.0:9981:8081 emqx/emqx:latest;

11 一篇文章不表述不了多少东西，也不能让许多同学尝鲜，这里我放出开源地址供同学们把玩

https://gitee.com/diystring/pchelper

注意：开源代码中的IP地址和有道的ID秘钥都是入门级配置和有免费额度限制的，所以同学们把玩的时候不用恶搞哈,尽量让更多的同学能下载F5尝鲜