.net .net framework 用多个声卡同时播放不同文本语音

在 .NET Framework 中，要同时使用多个声卡播放不同的文本语音，可以使用 DirectSound API 或者 Windows Multimedia API。下面是使用 Windows Multimedia API 的示例代码：

using System.Runtime.InteropServices;
using System.Threading;
using Microsoft.Win32.SafeHandles;

class Program
{
    // 声明 Win32 API 函数
    [DllImport("winmm.dll")]
    private static extern int waveOutGetNumDevs();

    [DllImport("winmm.dll")]
    private static extern int waveOutOpen(out IntPtr hWaveOut, int uDeviceID, ref WaveFormat lpFormat, IntPtr dwCallback, IntPtr dwInstance, int dwFlags);

    [DllImport("winmm.dll")]
    private static extern int waveOutPrepareHeader(IntPtr hWaveOut, ref WaveHeader lpWaveOutHdr, int uSize);

    [DllImport("winmm.dll")]
    private static extern int waveOutWrite(IntPtr hWaveOut, ref WaveHeader lpWaveOutHdr, int uSize);

    [DllImport("winmm.dll")]
    private static extern int waveOutClose(IntPtr hWaveOut);

    // 声明 WaveOutOpen 函数的参数结构体
    [StructLayout(LayoutKind.Sequential)]
    private struct WaveFormat
    {
        public short wFormatTag;
        public short nChannels;
        public int nSamplesPerSec;
        public int nAvgBytesPerSec;
        public short nBlockAlign;
        public short wBitsPerSample;
        public short cbSize;
    }

    // 声明 WaveOutPrepareHeader 函数的参数结构体
    [StructLayout(LayoutKind.Sequential)]
    private struct WaveHeader
    {
        public IntPtr lpData;
        public int dwBufferLength;
        public int dwBytesRecorded;
        public IntPtr dwUser;
        public int dwFlags;
        public int dwLoops;
        public IntPtr lpNext;
        public IntPtr reserved;
    }

    static void Main(string[] args)
    {
        int numDevices = waveOutGetNumDevs();
        if (numDevices < 2)
        {
            Console.WriteLine("没有足够的声卡！");
            return;
        }

        // 打开第一和第二个声卡
        IntPtr hWaveOut1, hWaveOut2;
        WaveFormat format = new WaveFormat() { wFormatTag = 1, nChannels = 1, nSamplesPerSec = 8000, wBitsPerSample = 8, nBlockAlign = 1, nAvgBytesPerSec = 8000 };
        waveOutOpen(out hWaveOut1, 0, ref format, IntPtr.Zero, IntPtr.Zero, 0);
        waveOutOpen(out hWaveOut2, 1, ref format, IntPtr.Zero, IntPtr.Zero, 0);

        // 打开两个语音文件
        SafeFileHandle fileHandle1 = CreateFile("audio1.wav", FileAccess.Read, FileShare.Read, IntPtr.Zero, FileMode.Open, FileAttributes.Normal, IntPtr.Zero);
        SafeFileHandle fileHandle2 = CreateFile("audio2.wav", FileAccess.Read, FileShare.Read, IntPtr.Zero, FileMode.Open, FileAttributes.Normal, IntPtr.Zero);
        IntPtr hFile1 = fileHandle1.DangerousGetHandle();
        IntPtr hFile2 = fileHandle2.DangerousGetHandle();

        // 准备两个语音文件的缓冲区
        const int BUFFER_SIZE = 4096;
        byte[] buffer1 = new byte[BUFFER_SIZE];
        byte[] buffer2 = new byte[BUFFER_SIZE];
        var header1 = new WaveHeader() { lpData = Marshal.AllocHGlobal(BUFFER_SIZE), dwBufferLength = BUFFER_SIZE, dwFlags = 0 };
        var header2 = new WaveHeader() { lpData = Marshal.AllocHGlobal(BUFFER_SIZE), dwBufferLength = BUFFER_SIZE, dwFlags = 0 };
        int bytesRead1 = 0, bytesRead2 = 0;
        ReadFile(hFile1, buffer1, BUFFER_SIZE, ref bytesRead1, IntPtr.Zero);
        ReadFile(hFile2, buffer2, BUFFER_SIZE, ref bytesRead2, IntPtr.Zero);
        Marshal.Copy(buffer1, 0, header1.lpData, bytesRead1);
        Marshal.Copy(buffer2, 0, header2.lpData, bytesRead2);
        waveOutPrepareHeader(hWaveOut1, ref header1, Marshal.SizeOf(typeof(WaveHeader)));
        waveOutPrepareHeader(hWaveOut2, ref header2, Marshal.SizeOf(typeof(WaveHeader)));

        // 开始播放两个语音文件
        waveOutWrite(hWaveOut1, ref header1, Marshal.SizeOf(typeof(WaveHeader)));
        waveOutWrite(hWaveOut2, ref header2, Marshal.SizeOf(typeof(WaveHeader)));

        // 等待播放完成
        while (header1.dwFlags != 1 || header2.dwFlags != 1)
        {
            Thread.Sleep(100);
        }

        // 关闭 WaveOut 和文件句柄
        waveOutClose(hWaveOut1);
        waveOutClose(hWaveOut2);
        fileHandle1.Close();
        fileHandle2.Close();

        // 释放缓冲区内存
        Marshal.FreeHGlobal(header1.lpData);
        Marshal.FreeHGlobal(header2.lpData);
    }

    // 声明 CreateFile 函数，用于打开语音文件
    [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    private static extern SafeFileHandle CreateFile(
        string lpFileName, FileAccess dwDesiredAccess, FileShare dwShareMode,
        IntPtr lpSecurityAttributes, FileMode dwCreationDisposition,
        FileAttributes dwFlagsAndAttributes, IntPtr hTemplateFile);

    // 声明 ReadFile 函数，用于从语音文件中读取数据
    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern bool ReadFile(IntPtr handle, byte[] bytes, int numBytesToRead, ref int numBytesRead, IntPtr overlapped);
}

上面的代码中，我们使用了 Windows Multimedia API 中的 WaveOutOpen、WaveOutPrepareHeader、WaveOutWrite 和 WaveOutClose 函数来播放语音文件。我们打开了两个声卡，并将两个语音文件分别设置到对应的声卡中。我们使用 SafeFileHandle 和 CreateFile 函数打开语音文件，并使用 ReadFile 函数从文件中读取数据，然后使用 WaveOutPrepareHeader 函数将数据设置到缓冲区中，最后使用 WaveOutWrite 函数播放缓冲区中的数据。我们在一个循环中等待语音文件播放完成，然后关闭相关的 WaveOut 和文件句柄，释放缓冲区内存。