如何在C# WinForm+Azure语音转文字中实现下拉框选择输入麦克风

实现步骤说明 #

1. 枚举系统麦克风设备

通过调用Windows原生winmm.dll API获取系统所有可用输入麦克风设备，填充到下拉框：

• waveInGetNumDevs()：获取输入设备总数
• waveInGetDevCaps()：读取单个设备的名称等详细信息
• FillSoundDevicesInCombobox()方法遍历设备列表，将设备信息添加到下拉框CB1

2. 持久化用户选择

利用WinForm内置的Properties.Settings保存用户的设备选择，重启应用后自动恢复：

• 窗体加载时（Form2_Load）：读取保存的设备信息，匹配下拉框选项并自动选中
• 确定按钮点击时（button1_Click）：将当前选中的设备信息保存到配置文件

3. 配置Azure语音服务使用选中设备

这是核心环节，需要在语音识别初始化代码中指定选中的麦克风设备ID（避免同名设备冲突）。以下是调整后的关键代码：

首先定义设备信息类，同时存储ID和名称：

public class AudioDeviceInfo
{
    public uint DeviceId { get; set; }
    public string DeviceName { get; set; }
    public override string ToString()
    {
        return DeviceName; // 下拉框显示设备名称
    }
}

修改设备填充方法，添加完整设备信息：

public void FillSoundDevicesInCombobox()
{
    uint devices = waveInGetNumDevs();
    WAVEOUTCAPS caps = new WAVEOUTCAPS();
    for (uint i = 0; i < devices; i++)
    {
        waveInGetDevCaps(i, ref caps, (uint)Marshal.SizeOf(caps));
        CB1.Items.Add(new AudioDeviceInfo { DeviceId = i, DeviceName = caps.szPname });
    }
}

在语音识别初始化时指定设备：

// 初始化Azure语音配置
var speechConfig = SpeechConfig.FromSubscription("你的Azure订阅密钥", "服务区域");
// 获取选中的设备
var selectedDevice = CB1.SelectedItem as AudioDeviceInfo;
if (selectedDevice != null)
{
    // 设置语音识别的输入设备ID
    speechConfig.SetProperty(SpeechConfigPropertyId.AudioConfigDeviceId, selectedDevice.DeviceId.ToString());
}
// 创建语音识别器
var recognizer = new SpeechRecognizer(speechConfig);

完整整合代码 #

using System;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using Microsoft.CognitiveServices.Speech;

namespace WindowsFormsApp2
{
    public partial class Form2 : Form
    {
        [DllImport("winmm.dll", SetLastError = true)]
        static extern uint waveInGetNumDevs();

        [DllImport("winmm.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern uint waveInGetDevCaps(uint hwo, ref WAVEOUTCAPS pwoc, uint cbwoc);

        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
        public struct WAVEOUTCAPS
        {
            public ushort wMid;
            public ushort wPid;
            public uint vDriverVersion;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]
            public string szPname;
            public uint dwFormats;
            public ushort wChannels;
            public ushort wReserved1;
            public uint dwSupport;
        }

        public class AudioDeviceInfo
        {
            public uint DeviceId { get; set; }
            public string DeviceName { get; set; }
            public override string ToString()
            {
                return DeviceName;
            }
        }

        public void FillSoundDevicesInCombobox()
        {
            uint devices = waveInGetNumDevs();
            WAVEOUTCAPS caps = new WAVEOUTCAPS();
            for (uint i = 0; i < devices; i++)
            {
                waveInGetDevCaps(i, ref caps, (uint)Marshal.SizeOf(caps));
                CB1.Items.Add(new AudioDeviceInfo { DeviceId = i, DeviceName = caps.szPname });
            }
        }
      
        public Form2()
        {
            InitializeComponent();
        }

        private void Form2_Load(object sender, EventArgs e)
        {
            FillSoundDevicesInCombobox();

            // 加载上次保存的设备选择
            if (!string.IsNullOrWhiteSpace(Properties.Settings.Default.SelectedAudioDeviceId))
            {
                uint savedId = uint.Parse(Properties.Settings.Default.SelectedAudioDeviceId);
                var item = CB1.Items.Cast<AudioDeviceInfo>().FirstOrDefault(x => x.DeviceId == savedId);
                if (item != null)
                    CB1.SelectedItem = item;
            }

            checkBox1.Checked = Properties.Settings.Default.Punctuation;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            var selectedDevice = CB1.SelectedItem as AudioDeviceInfo;
            if (selectedDevice != null)
            {
                Properties.Settings.Default.SelectedAudioDeviceId = selectedDevice.DeviceId.ToString();
                Properties.Settings.Default.SelectedAudioDeviceName = selectedDevice.DeviceName;
            }
            Properties.Settings.Default.Punctuation = checkBox1.Checked;
            Properties.Settings.Default.Save();
            Close();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Close();
        }
    }
}

注意事项 #

• 需提前安装Microsoft.CognitiveServices.Speech NuGet包
• 替换代码中的Azure订阅密钥和服务区域
• 优先使用设备ID匹配，避免同名设备导致的识别错误

内容的提问来源于stack exchange，提问作者Babar Ali