c#如何使用waveOut发声

在 C# 中使用 waveOut 发声可以通过以下步骤实现：

1. 引用 Windows API 函数库 winmm.dll，使用以下语句：

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

2. 定义 WAVEFORMATEX 结构体，用于设置音频格式：

[StructLayout(LayoutKind.Sequential, Pack = 2)]
struct WAVEFORMATEX
{
    public short wFormatTag;
    public short nChannels;
    public int nSamplesPerSec;
    public int nAvgBytesPerSec;
    public short nBlockAlign;
    public short wBitsPerSample;
    public short cbSize;
}

3. 创建音频缓冲区，使用以下语句：

IntPtr hWaveOut; // waveOut 句柄
WAVEFORMATEX format = new WAVEFORMATEX
{
    wFormatTag = 1,
    nChannels = 1,
    nSamplesPerSec = 8000,
    nAvgBytesPerSec = 8000,
    nBlockAlign = 1,
    wBitsPerSample = 8,
    cbSize = 0
};
waveOutOpen(out hWaveOut, 0, ref format, null, IntPtr.Zero, 0);

4. 将音频数据写入缓冲区，使用以下语句：

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

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

byte[] buffer = new byte[8000];
IntPtr hBuffer = Marshal.AllocHGlobal(buffer.Length);
Marshal.Copy(buffer, 0, hBuffer, buffer.Length);

IntPtr hHeader = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(WAVEHDR)));
WAVEHDR header = new WAVEHDR
{
    lpData = hBuffer,
    dwBufferLength = (uint)buffer.Length,
    dwBytesRecorded = 0,
    dwUser = IntPtr.Zero,
    dwFlags = 0,
    dwLoops = 0,
    lpNext = IntPtr.Zero,
    reserved = IntPtr.Zero
};
Marshal.StructureToPtr(header, hHeader, false);

waveOutPrepareHeader(hWaveOut, hHeader, (uint)Marshal.SizeOf(typeof(WAVEHDR)));
waveOutWrite(hWaveOut, hHeader, (uint)Marshal.SizeOf(typeof(WAVEHDR)));

以上就是使用 waveOut 在 C# 中发声的基本步骤，具体可以根据实际需求进行调整。