C# Windows 11 提供的 Bluetooth API实现蓝牙的扫描、配对、通信 例程

以下是一个 C# Windows 11 的示例代码，演示如何使用 Bluetooth API 实现蓝牙设备的扫描、配对、通信：

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Windows.Devices.Bluetooth;
using Windows.Devices.Bluetooth.GenericAttributeProfile;
using Windows.Devices.Enumeration;

class Program
{
    static BluetoothLEDevice device;
    static GattCharacteristic characteristic;

    static async Task Main(string[] args)
    {
        // 建立连接前，先扫描设备列表并选择要连接的设备
        DeviceInformationCollection devices = await BluetoothLEDevice.GetDeviceSelector().FindAllAsync();
        Console.WriteLine("Found devices:");
        for (int i = 0; i < devices.Count; i++)
        {
            Console.WriteLine($"{i + 1}. {devices[i].Name}");
        }
        string selection = Console.ReadLine();
        int selectedIndex;
        if (!int.TryParse(selection, out selectedIndex) || selectedIndex < 1 || selectedIndex > devices.Count)
        {
            Console.WriteLine("Invalid selection.");
            return;
        }
        DeviceInformation selectedDevice = devices[selectedIndex - 1];

        // 连接设备并获取服务和特征
        device = await BluetoothLEDevice.FromIdAsync(selectedDevice.Id);
        GattDeviceServicesResult servicesResult = await device.GetGattServicesAsync();
        if (servicesResult.Status != GattCommunicationStatus.Success)
        {
            Console.WriteLine($"Failed to get services. Status: {servicesResult.Status}");
            return;
        }
        GattDeviceService service = servicesResult.Services[0];
        GattCharacteristicsResult characteristicsResult = await service.GetCharacteristicsAsync();
        if (characteristicsResult.Status != GattCommunicationStatus.Success)
        {
            Console.WriteLine($"Failed to get characteristics. Status: {characteristicsResult.Status}");
            return;
        }
        characteristic = characteristicsResult.Characteristics[0];

        // 订阅特征的值改变事件
        characteristic.ValueChanged += Characteristic_ValueChanged;
        GattCommunicationStatus status = await characteristic.WriteClientCharacteristicConfigurationDescriptorAsync(GattClientCharacteristicConfigurationDescriptorValue.Notify);
        if (status != GattCommunicationStatus.Success)
        {
            Console.WriteLine($"Failed to subscribe to value changes. Status: {status}");
            return;
        }

        // 等待用户输入并向设备写入数据
        Console.WriteLine("Connected to device. Enter message to send: ");
        string message = Console.ReadLine();
        byte[] data = System.Text.Encoding.UTF8.GetBytes(message);
        GattWriteResult writeResult = await characteristic.WriteValueAsync(data.AsBuffer());
        if (writeResult.Status != GattCommunicationStatus.Success)
        {
            Console.WriteLine($"Failed to write value. Status: {writeResult.Status}");
            return;
        }

        Console.WriteLine("Data sent. Press any key to exit.");
        Console.ReadKey();

        // 断开连接并清理资源
        characteristic.ValueChanged -= Characteristic_ValueChanged;
        await characteristic.WriteClientCharacteristicConfigurationDescriptorAsync(GattClientCharacteristicConfigurationDescriptorValue.None);
        device.Dispose();
    }

    private static void Characteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
    {
        byte[] data = args.CharacteristicValue.ToArray();
        string message = System.Text.Encoding.UTF8.GetString(data);
        Console.WriteLine($"Received message: {message}");
    }
}

此代码首先扫描蓝牙设备列表并让用户选择要连接的设备。然后它连接设备并获取服务和特征。接下来，它订阅特征值改变事件，并等待用户输入要发送的消息。一旦用户输入消息，它将其转换为字节数组并向特征写入数据。它还打印从设备接收到的任何消息。最后，当用户按下任何键时，它将断开连接并清理资源。