好的，这里是：
const int MAXPNAMELEN = 32;const int MIXER_SHORT_NAME_CHARS = 16;const int MIXER_LONG_NAME_CHARS = 64;[Flags] enum MIXERLINE_LINEF : uint{ ACTIVE = 0x00000001, DISConNECTED = 0x00008000, SOURCE = 0x80000000}[Flags] enum MIXER: uint{ GETLINEINFOF_DESTINATION = 0x00000000, GETLINEINFOF_SOURCE = 0x00000001, GETLINEINFOF_LINEID = 0x00000002, GETLINEINFOF_COMPonENTTYPE = 0x00000003, GETLINEINFOF_TARGETTYPE = 0x00000004, GETLINEINFOF_QUERYMASK = 0x0000000F, GETLINECONTROLSF_ALL = 0x00000000, GETLINECONTROLSF_onEBYID = 0x00000001, GETLINECONTROLSF_onEBYTYPE = 0x00000002, GETLINECONTROLSF_QUERYMASK = 0x0000000F, GETCONTROLDETAILSF_VALUE = 0x00000000, GETCONTROLDETAILSF_LISTTEXT = 0x00000001, GETCONTROLDETAILSF_QUERYMASK = 0x0000000F, OBJECTF_MIXER = 0x00000000, OBJECTF_WAVEOUT = 0x10000000, OBJECTF_WAVEIN = 0x20000000, OBJECTF_MIDIOUT = 0x30000000, OBJECTF_MIDIIN = 0x40000000, OBJECTF_AUX = 0x50000000, OBJECTF_HANDLE = 0x80000000, OBJECTF_HMIXER = OBJECTF_HANDLE | OBJECTF_MIXER, OBJECTF_HWAVEOUT = OBJECTF_HANDLE | OBJECTF_WAVEOUT, OBJECTF_HWAVEIN = OBJECTF_HANDLE | OBJECTF_WAVEIN, OBJECTF_HMIDIOUT = OBJECTF_HANDLE | OBJECTF_MIDIOUT, OBJECTF_HMIDIIN = OBJECTF_HANDLE | OBJECTF_MIDIIN}[Flags] enum MIXERCONTROL_CT : uint{ CLASS_MASK = 0xF0000000, CLASS_CUSTOM = 0x00000000, CLASS_METER = 0x10000000, CLASS_SWITCH = 0x20000000, CLASS_NUMBER = 0x30000000, CLASS_SLIDER = 0x40000000, CLASS_FADER = 0x50000000, CLASS_TIME = 0x60000000, CLASS_LIST = 0x70000000, SUBCLASS_MASK = 0x0F000000, SC_SWITCH_BOOLEAN = 0x00000000, SC_SWITCH_BUTTON = 0x01000000, SC_METER_POLLED = 0x00000000, SC_TIME_MICROSECS = 0x00000000, SC_TIME_MILLISECS = 0x01000000, SC_LIST_SINGLE = 0x00000000, SC_LIST_MULTIPLE = 0x01000000, UNITS_MASK = 0x00FF0000, UNITS_CUSTOM = 0x00000000, UNITS_BOOLEAN = 0x00010000, UNITS_SIGNED = 0x00020000, UNITS_UNSIGNED = 0x00030000, UNITS_DECIBELS = 0x00040000, UNITS_PERCENT = 0x00050000, }[Flags] enum MIXERCONTROL_ConTROLTYPE : uint{ CUSTOM = MIXERCONTROL_CT.CLASS_CUSTOM | MIXERCONTROL_CT.UNITS_CUSTOM, BOOLEANMETER = MIXERCONTROL_CT.CLASS_METER | MIXERCONTROL_CT.SC_METER_POLLED | MIXERCONTROL_CT.UNITS_BOOLEAN, SIGNEDMETER = MIXERCONTROL_CT.CLASS_METER | MIXERCONTROL_CT.SC_METER_POLLED | MIXERCONTROL_CT.UNITS_SIGNED, PEAKMETER = SIGNEDMETER + 1, UNSIGNEDMETER = MIXERCONTROL_CT.CLASS_METER | MIXERCONTROL_CT.SC_METER_POLLED | MIXERCONTROL_CT.UNITS_UNSIGNED, BOOLEAN = MIXERCONTROL_CT.CLASS_SWITCH | MIXERCONTROL_CT.SC_SWITCH_BOOLEAN | MIXERCONTROL_CT.UNITS_BOOLEAN, onOFF = BOOLEAN + 1, MUTE= BOOLEAN + 2, MONO= BOOLEAN + 3, LOUDNESS = BOOLEAN + 4, STEREOENH = BOOLEAN + 5, BASS_BOOST = BOOLEAN + 0x00002277, BUTTON = MIXERCONTROL_CT.CLASS_SWITCH | MIXERCONTROL_CT.SC_SWITCH_BUTTON | MIXERCONTROL_CT.UNITS_BOOLEAN, DECIBELS = MIXERCONTROL_CT.CLASS_NUMBER | MIXERCONTROL_CT.UNITS_DECIBELS, SIGNED = MIXERCONTROL_CT.CLASS_NUMBER | MIXERCONTROL_CT.UNITS_SIGNED, UNSIGNED = MIXERCONTROL_CT.CLASS_NUMBER | MIXERCONTROL_CT.UNITS_UNSIGNED, PERCENT = MIXERCONTROL_CT.CLASS_NUMBER | MIXERCONTROL_CT.UNITS_PERCENT, SLIDER = MIXERCONTROL_CT.CLASS_SLIDER | MIXERCONTROL_CT.UNITS_SIGNED, PAN = SLIDER + 1, QSOUNDPAN = SLIDER + 2, FADER = MIXERCONTROL_CT.CLASS_FADER | MIXERCONTROL_CT.UNITS_UNSIGNED, VOLUME = FADER + 1, BASS= FADER + 2, TREBLE = FADER + 3, EQUALIZER = FADER + 4, SINGLESELECT = MIXERCONTROL_CT.CLASS_LIST | MIXERCONTROL_CT.SC_LIST_SINGLE | MIXERCONTROL_CT.UNITS_BOOLEAN, MUX = SINGLESELECT + 1, MULTIPLESELECT = MIXERCONTROL_CT.CLASS_LIST | MIXERCONTROL_CT.SC_LIST_MULTIPLE | MIXERCONTROL_CT.UNITS_BOOLEAN, MIXER = MULTIPLESELECT + 1, MICROTIME = MIXERCONTROL_CT.CLASS_TIME | MIXERCONTROL_CT.SC_TIME_MICROSECS | MIXERCONTROL_CT.UNITS_UNSIGNED, MILLITIME = MIXERCONTROL_CT.CLASS_TIME | MIXERCONTROL_CT.SC_TIME_MILLISECS | MIXERCONTROL_CT.UNITS_UNSIGNED}[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]struct MIXERLINE{ [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)] public struct TargetInfo{ public uint dwType; public uint dwDeviceID; public ushort wMid; public ushort wPid; public uint vDriverVersion; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=MAXPNAMELEN)] public string szPname; } public uint cbStruct; public uint dwDestination; public uint dwSource; public uint dwLineID; public MIXERLINE_LINEF fdwLine; public uint dwUser; public uint dwComponentType; public uint cChannels; public uint cConnection; public uint cControls; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=MIXER_SHORT_NAME_CHARS)] public string szShortName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=MIXER_LONG_NAME_CHARS)] public string szName; public TargetInfo Target;}[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]struct MIXERCONTROL{ [StructLayout(LayoutKind.Explicit)] public struct BoundsInfo{ [FieldOffset(0)] public int lMinimum; [FieldOffset(4)] public int lMaximum; [FieldOffset(0)] public uint dwMinimum; [FieldOffset(4)] public uint dwMaximum; [FieldOffset(8), MarshalAs(UnmanagedType.ByValArray, SizeConst=4)] public uint[] dwReserved; } [StructLayout(LayoutKind.Explicit)] public struct MetricsInfo{ [FieldOffset(0)] public uint cSteps; [FieldOffset(0)] public uint cbCustomData; [FieldOffset(4), MarshalAs(UnmanagedType.ByValArray, SizeConst=5)] public uint[] dwReserved; } public uint cbStruct; public uint dwControlID; public MIXERCONTROL_ConTROLTYPE dwControlType; public uint fdwControl; public uint cMultipleItems; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=MIXER_SHORT_NAME_CHARS)] public string szShortName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst=MIXER_LONG_NAME_CHARS)] public string szName; public BoundsInfo Bounds; public MetricsInfo Metrics;}[StructLayout(LayoutKind.Explicit)]struct MIXERLINECONTROLS{ [FieldOffset(0)] public uint cbStruct; [FieldOffset(4)] public uint dwLineID; [FieldOffset(8)] public uint dwControlID; [FieldOffset(8)] // not a typo! overlaps previous field public uint dwControlType; [FieldOffset(12)] public uint cControls; [FieldOffset(16)] public uint cbmxctrl; [FieldOffset(20)] public IntPtr pamxctrl;}[StructLayout(LayoutKind.Explicit)]struct MIXERCONTROLDETAILS{ [FieldOffset(0)] public uint cbStruct; [FieldOffset(4)] public uint dwControlID; [FieldOffset(8)] public uint cChannels; [FieldOffset(12)] public IntPtr hwndOwner; [FieldOffset(12)] // not a typo! public uint cMultipleItems; [FieldOffset(16)] public uint cbDetails; [FieldOffset(20)] public IntPtr paDetails;}[StructLayout(LayoutKind.Sequential)]struct VOLUME{ public int left; public int right;}struct MixerInfo{ public uint volumeCtl; public uint muteCtl; public int minVolume; public int maxVolume;}[Dllimport("WinMM.dll", CharSet=CharSet.Auto)]static extern uint mixerGetLineInfo (IntPtr hmxobj, ref MIXERLINE pmxl, MIXER flags);[Dllimport("WinMM.dll", CharSet=CharSet.Auto)]static extern uint mixerGetLineControls (IntPtr hmxobj, ref MIXERLINEConTROLS pmxlc, MIXER flags);[Dllimport("WinMM.dll", CharSet=CharSet.Auto)]static extern uint mixerGetControlDetails(IntPtr hmxobj, ref MIXERConTROLDETAILS pmxcd, MIXER flags);[Dllimport("WinMM.dll", CharSet=CharSet.Auto)]static extern uint mixerSetControlDetails(IntPtr hmxobj, ref MIXERConTROLDETAILS pmxcd, MIXER flags);static MixerInfo GetMixerControls(){ MIXERLINE mxl = new MIXERLINE(); MIXERLINEConTROLS mlc = new MIXERLINEConTROLS(); mxl.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERLINE)); mlc.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERLINECONTROLS)); mixerGetLineInfo(IntPtr.Zero, ref mxl, MIXER.OBJECTF_MIXER | MIXER.GETLINEINFOF_DESTINATION); mlc.dwLineID = mxl.dwLineID; mlc.cControls = mxl.cControls; mlc.cbmxctrl = (uint)Marshal.SizeOf(typeof(MIXERCONTROL)); mlc.pamxctrl = Marshal.AllocHGlobal((int)(mlc.cbmxctrl * mlc.cControls)); mixerGetLineControls(IntPtr.Zero, ref mlc, MIXER.OBJECTF_MIXER | MIXER.GETLINECONTROLSF_ALL); MixerInfo rtn = new MixerInfo(); for(int i = 0; i < mlc.cControls; i++){ MIXERConTROL mxc = (MIXERCONTROL)Marshal.PtrToStructure((IntPtr)((int)mlc.pamxctrl + (int)mlc.cbmxctrl * i), typeof(MIXERCONTROL)); switch(mxc.dwControlType){ case MIXERCONTROL_CONTROLTYPE.VOLUME: rtn.volumeCtl = mxc.dwControlID; rtn.minVolume = mxc.Bounds.lMinimum; rtn.maxVolume = mxc.Bounds.lMaximum; break; case MIXERCONTROL_CONTROLTYPE.MUTE: rtn.muteCtl = mxc.dwControlID; break; } } Marshal.FreeHGlobal(mlc.pamxctrl); return rtn;}static VOLUME GetVolume(MixerInfo mi){ MIXERConTROLDETAILS mcd = new MIXERConTROLDETAILS(); mcd.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERCONTROLDETAILS)); mcd.dwControlID = mi.volumeCtl; mcd.cMultipleItems = 0; mcd.cChannels = 2; mcd.cbDetails = (uint)Marshal.SizeOf(typeof(int)); mcd.paDetails = Marshal.AllocHGlobal((int)mcd.cbDetails); mixerGetControlDetails(IntPtr.Zero, ref mcd, MIXER.GETCONTROLDETAILSF_VALUE | MIXER.OBJECTF_MIXER); VOLUME rtn = (VOLUME)Marshal.PtrToStructure(mcd.paDetails, typeof(VOLUME)); Marshal.FreeHGlobal(mcd.paDetails); return rtn;}static bool IsMuted(MixerInfo mi){ MIXERConTROLDETAILS mcd = new MIXERConTROLDETAILS(); mcd.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERCONTROLDETAILS)); mcd.dwControlID = mi.muteCtl; mcd.cMultipleItems = 0; mcd.cChannels = 1; mcd.cbDetails = 4; mcd.paDetails = Marshal.AllocHGlobal((int)mcd.cbDetails); mixerGetControlDetails(IntPtr.Zero, ref mcd, MIXER.GETCONTROLDETAILSF_VALUE | MIXER.OBJECTF_MIXER); int rtn = Marshal.ReadInt32(mcd.paDetails); Marshal.FreeHGlobal(mcd.paDetails); return rtn != 0;}static void AdjustVolume(MixerInfo mi, int delta){ VOLUME volume = GetVolume(mi); if(delta > 0){ volume.left = Math.Min(mi.maxVolume, volume.left + delta); volume.right = Math.Min(mi.maxVolume, volume.right + delta); }else{ volume.left = Math.Max(mi.minVolume, volume.left + delta); volume.right = Math.Max(mi.minVolume, volume.right + delta); } SetVolume(mi, volume);}static void SetVolume(MixerInfo mi, VOLUME volume){ MIXERConTROLDETAILS mcd = new MIXERConTROLDETAILS(); mcd.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERCONTROLDETAILS)); mcd.dwControlID = mi.volumeCtl; mcd.cMultipleItems = 0; mcd.cChannels = 2; mcd.cbDetails = (uint)Marshal.SizeOf(typeof(int)); mcd.paDetails = Marshal.AllocHGlobal((int)mcd.cbDetails); Marshal.StructureToPtr(volume, mcd.paDetails, false); mixerSetControlDetails(IntPtr.Zero, ref mcd, MIXER.GETCONTROLDETAILSF_VALUE | MIXER.OBJECTF_MIXER); Marshal.FreeHGlobal(mcd.paDetails);}static void SetMute(MixerInfo mi, bool mute){ MIXERConTROLDETAILS mcd = new MIXERConTROLDETAILS(); mcd.cbStruct = (uint)Marshal.SizeOf(typeof(MIXERCONTROLDETAILS)); mcd.dwControlID = mi.muteCtl; mcd.cMultipleItems = 0; mcd.cChannels = 1; mcd.cbDetails = 4; mcd.paDetails = Marshal.AllocHGlobal((int)mcd.cbDetails); Marshal.WriteInt32(mcd.paDetails, mute ? 1 : 0); mixerSetControlDetails(IntPtr.Zero, ref mcd, MIXER.GETCONTROLDETAILSF_VALUE | MIXER.OBJECTF_MIXER); Marshal.FreeHGlobal(mcd.paDetails);}此代码庞大而丑陋。它是对某些C ++代码的翻译，并且由于必须定义所有P /
Invoke内容，因此代码很多。但我已经对其进行了测试，并且可以正常工作。要使用它，您只需要类似：
MixerInfo mi = GetMixerControls();AdjustVolume(mi, 100); // add 100 to the current volume
要么
MixerInfo mi = GetMixerControls();AdjustVolume(mi, (mi.maxVolume - mi.minVolume) / 10); // increase the volume by 10% of total range
要么
MixerInfo mi = GetMixerControls();SetVolume(mi, mi.maxVolume); // let's get this party crunk'd!
要么
MixerInfo mi = GetMixerControls();SetMute(mi, true); // shhhh!!!!!!
警告
由于使用了固定大小的整数和字段偏移量，因此在64位Windows上，这可能会失败。我不知道，我还没有测试过，也没有足够的注意力来知道这些字段的大小是否扩展到64位。
警告
编辑
为了简单起见（相对而言），我省略了任何错误处理。您应该真正检查所有mixerXXX函数的返回码，但是我将其留给读者作为练习（阅读为：我懒得这样做）。
