我发现这个答案建议使用“core audio.dll”API和以下代码：
private function getmute() as boolean
Dim devenum As New MMDeviceEnumerator
Dim device As MMDevice = devenum.GetDefaultAudioEndpoint(EDataFlow.eRender, ERole.eMultimedia)
If device.AudioEndpointVolume.Mute = True Then
Return True
Else
Return False
End If
End Function
我尝试了该代码，但它不起作用，而且我无法对其他问题发表评论。
当我尝试上面的代码时，以下行抛出异常：
If device.AudioEndpointVolume.Mute = True Then
这是异常消息：
AudioEndpointVolume 不是设备的成员。
我已经导入了
CoreAudioAPI我正在寻找
VB.NETC#VB.NetCoreAudio API代码封装在
ClassCoreAudioIsMuted()有关 MSDN 上的 Windows CoreAudio API 的更多信息。
GitHub NAudio CoreAudioApi 实现 (
C#实施方法：
IsMuted() As IntegerSetMute(Boolean)True/FalseIsMediadPlaying()GetVolume() As Integer0 to 100SetVolume(Integer)0 to 100VolumeUp()VolumeDown()用途：
Dim isMuted As Boolean = AudioDevice.IsMuted()
' True=Mutes the Audio, False=Un-Mutes (?) it
AudioDevice.SetMute(True)
' Checks whether the Media Device currently playing
Dim isPlaying As Boolean = AudioDevice.IsMediadPlaying()
Dim volume As Integer = AudioDevice.GetVolume()
' Sets the Audio level to 50%, returns the previous value
Dim previousVolume As Integer = AudioDevice.SetVolume(50)
' Increases the Audio level by 1 Step
AudioDevice.VolumeUp()
' Decreases the Audio level by 1 Step
AudioDevice.VolumeDown()
声明：
Imports System
Imports System.Runtime.InteropServices
Public Class AudioDevice
Friend Enum EDataFlow
eRender
eCapture
eAll
EDataFlow_enum_count
End Enum
Friend Enum ERole
eConsole
eMultimedia
eCommunications
ERole_enum_count
End Enum
<Flags>
Public Enum CLSCTX As UInteger
CLSCTX_INPROC_SERVER = &H1
CLSCTX_INPROC_HANDLER = &H2
CLSCTX_LOCAL_SERVER = &H4
CLSCTX_INPROC_SERVER16 = &H8
CLSCTX_REMOTE_SERVER = &H10
CLSCTX_INPROC_HANDLER16 = &H20
CLSCTX_RESERVED1 = &H40
CLSCTX_RESERVED2 = &H80
CLSCTX_RESERVED3 = &H100
CLSCTX_RESERVED4 = &H200
CLSCTX_NO_CODE_DOWNLOAD = &H400
CLSCTX_RESERVED5 = &H800
CLSCTX_NO_CUSTOM_MARSHAL = &H1000
CLSCTX_ENABLE_CODE_DOWNLOAD = &H2000
CLSCTX_NO_FAILURE_LOG = &H4000
CLSCTX_DISABLE_AAA = &H8000
CLSCTX_ENABLE_AAA = &H10000
CLSCTX_FROM_DEFAULT_CONTEXT = &H20000
CLSCTX_ACTIVATE_32_BIT_SERVER = &H40000
CLSCTX_ACTIVATE_64_BIT_SERVER = &H80000
CLSCTX_INPROC = CLSCTX_INPROC_SERVER Or CLSCTX_INPROC_HANDLER
CLSCTX_SERVER = CLSCTX_INPROC_SERVER Or CLSCTX_LOCAL_SERVER Or CLSCTX_REMOTE_SERVER
CLSCTX_ALL = CLSCTX_SERVER Or CLSCTX_INPROC_HANDLER
End Enum
<ComImport, Guid("BCDE0395-E52F-467C-8E3D-C4579291692E")>
Public Class MMDeviceEnumeratorComObject
End Class
<ComImport, Guid("A95664D2-9614-4F35-A746-DE8DB63617E6"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)>
Friend Interface IMMDeviceEnumerator
Function NotImpl1() As Integer
Function GetDefaultAudioEndpoint(
dataFlow As EDataFlow,
role As ERole,
<Out> ByRef ppDevice As IMMDevice) As Integer
End Interface
<ComImport, Guid("D666063F-1587-4E43-81F1-B948E807363F"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)>
Public Interface IMMDevice
Function Activate(<MarshalAs(UnmanagedType.LPStruct)> iid As Guid,
dwClsCtx As CLSCTX, pActivationParams As IntPtr) As <MarshalAs(UnmanagedType.IUnknown)> Object
'Function Activate(ByRef iid As Guid, dwClsCtx As CLSCTX, pActivationParams As IntPtr, <Out> ByRef ppInterface As IAudioEndpointVolume) As Integer
End Interface
<ComImport, Guid("5CDF2C82-841E-4546-9722-0CF74078229A"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)>
Public Interface IAudioEndpointVolume
Function RegisterControlChangeNotify(pNotify As IAudioEndpointVolumeCallback) As Integer
Function UnregisterControlChangeNotify(pNotify As IAudioEndpointVolumeCallback) As Integer
Function GetChannelCount(ByRef channelCount As Integer) As Integer
Function SetMasterVolumeLevel() As Integer
Function SetMasterVolumeLevelScalar(level As Single, eventContext As Guid) As Integer
Function GetMasterVolumeLevel(<Out> ByRef level As Single) As Integer
Function GetMasterVolumeLevelScalar(<Out> ByRef level As Single) As Integer
Function SetChannelVolumeLevel(channelNumber As Integer, level As Single, eventContext As Guid) As Integer
Function SetChannelVolumeLevelScalar(channelNumber As Integer, level As Single, eventContext As Guid) As Integer
Function GetChannelVolumeLevel(channelNumber As Integer, <Out> ByRef level As Single) As Integer
Function GetChannelVolumeLevelScalar(channelNumber As Integer, <Out> ByRef level As Single) As Integer
Function SetMute(<MarshalAs(UnmanagedType.Bool)> isMuted As Boolean, eventContext As Guid) As Integer
Function GetMute(<Out> ByRef isMuted As Boolean) As Integer
Function GetVolumeStepInfo(<Out> ByRef pnStep As Integer, ByRef pnStepCount As Integer) As Integer
Function VolumeStepUp(eventContext As Guid) As Integer
Function VolumeStepDown(eventContext As Guid) As Integer
Function QueryHardwareSupport(<Out> ByRef hardwareSupportMask As Integer) As Integer
Function GetVolumeRange(<Out> ByRef volumeMin As Single, <Out> ByRef volumeMax As Single, <Out> ByRef volumeStep As Single) As Integer
End Interface
<ComImport, Guid("657804FA-D6AD-4496-8A60-352752AF4F89"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)>
Public Interface IAudioEndpointVolumeCallback
<PreserveSig()>
Function OnNotify(pNotifyData As IntPtr) As Integer ' HRESULT
End Interface
<InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("C02216F6-8C67-4B5B-9D00-D008E73E0064")>
Public Interface IAudioMeterInformation
Function GetPeakValue() As Single
End Interface
Public Shared Function IsMuted() As Boolean
Dim masterVol As IAudioEndpointVolume = GetMasterVolumeObject()
Try
If masterVol Is Nothing Then
Throw New ApplicationException("Master Volume not available")
End If
Dim isAudioMuted As Boolean
masterVol.GetMute(isAudioMuted)
Return isAudioMuted
Finally
If masterVol IsNot Nothing Then
If masterVol IsNot Nothing Then Marshal.ReleaseComObject(masterVol)
End If
End Try
End Function
Public Shared Sub SetMute(IsMute As Boolean)
Dim masterVol As IAudioEndpointVolume = GetMasterVolumeObject()
Try
masterVol.SetMute(IsMute, Guid.Empty)
Finally
If masterVol IsNot Nothing Then
If masterVol IsNot Nothing Then Marshal.ReleaseComObject(masterVol)
End If
End Try
End Sub
Public Shared Function IsMediadPlaying() As Boolean
Dim mediaDevice As IMMDevice = Nothing
Try
mediaDevice = GetDefaultAudioEndpoint()
Dim meter = mediaDevice.Activate(GetType(IAudioMeterInformation).GUID, CLSCTX.CLSCTX_ALL, IntPtr.Zero)
Dim value As Single = DirectCast(meter, IAudioMeterInformation).GetPeakValue()
Return value > 0.00000001F
Finally
If mediaDevice IsNot Nothing Then Marshal.ReleaseComObject(mediaDevice)
End Try
End Function
Public Shared Function GetVolume() As Integer
Dim fVolume As Single
Dim masterVol As IAudioEndpointVolume = GetMasterVolumeObject()
Try
masterVol.GetMasterVolumeLevelScalar(fVolume)
Return CType(fVolume * 100, Integer)
Finally
If masterVol IsNot Nothing Then Marshal.ReleaseComObject(masterVol)
End Try
End Function
Public Shared Function SetVolume(volume As Integer) As Integer
volume = Math.Max(Math.Min(volume, 100), 0)
Dim masterVolume As IAudioEndpointVolume = GetMasterVolumeObject()
Try
Dim prevVolume = GetVolume()
masterVolume.SetMasterVolumeLevelScalar(volume / 100.0F, Guid.Empty)
Return prevVolume
Finally
If masterVolume IsNot Nothing Then Marshal.ReleaseComObject(masterVolume)
End Try
End Function
Public Shared Sub VolumeUp()
Dim masterVol As IAudioEndpointVolume = GetMasterVolumeObject()
Try
masterVol.VolumeStepUp(Guid.Empty)
Finally
If masterVol IsNot Nothing Then Marshal.ReleaseComObject(masterVol)
End Try
End Sub
Public Shared Sub VolumeDown()
Dim masterVol As IAudioEndpointVolume = GetMasterVolumeObject()
Try
masterVol.VolumeStepDown(Guid.Empty)
Finally
If masterVol IsNot Nothing Then Marshal.ReleaseComObject(masterVol)
End Try
End Sub
Friend Shared Function GetMasterVolumeObject() As IAudioEndpointVolume
Dim mediaDevice As IMMDevice = GetDefaultAudioEndpoint()
Try
Dim ppEndpoint = mediaDevice.Activate(GetType(IAudioEndpointVolume).GUID, CLSCTX.CLSCTX_ALL, IntPtr.Zero)
Return DirectCast(ppEndpoint, IAudioEndpointVolume)
Finally
If mediaDevice IsNot Nothing Then Marshal.ReleaseComObject(mediaDevice)
End Try
End Function
Public Shared Function GetDefaultAudioEndpoint() As IMMDevice
Dim mediaDevice As IMMDevice = Nothing
Dim deviceEnumerator = DirectCast(New MMDeviceEnumeratorComObject(), IMMDeviceEnumerator)
Try
deviceEnumerator.GetDefaultAudioEndpoint(EDataFlow.eRender, ERole.eMultimedia, mediaDevice)
Return mediaDevice
Finally
If deviceEnumerator IsNot Nothing Then Marshal.ReleaseComObject(deviceEnumerator)
End Try
End Function
End Class
使用 C/C++ 并了解一些 directshow 的知识非常简单，但使用 C# 时，您需要某种包装器来进行调用。老实说，我不使用托管语言来使用低级库，但我可能找到了适合您的情况的代码：
private int IsMuted() {
IAudioEndpointVolume masterVol = null;
try {
masterVol = GetMasterVolumeObject();
if( masterVol == null )
return -1; //error
bool isMuted;
masterVol.GetMute( out isMuted );
return Convert.ToInt32( isMuted );
}
finally {
if( masterVol != null )
Marshal.ReleaseComObject( masterVol );
}
}
private IAudioEndpointVolume GetMasterVolumeObject() {
IMMDeviceEnumerator deviceEnumerator = null;
IMMDevice speakers = null;
try {
deviceEnumerator = (IMMDeviceEnumerator)( new MMDeviceEnumerator() );
deviceEnumerator.GetDefaultAudioEndpoint( EDataFlow.eRender, ERole.eMultimedia, out speakers );
Guid IID_IAudioEndpointVolume = typeof( IAudioEndpointVolume ).GUID;
object o;
speakers.Activate( ref IID_IAudioEndpointVolume, 0, IntPtr.Zero, out o );
IAudioEndpointVolume masterVol = (IAudioEndpointVolume)o;
return masterVol;
}
finally {
if( speakers != null ) Marshal.ReleaseComObject( speakers );
if( deviceEnumerator != null ) Marshal.ReleaseComObject( deviceEnumerator );
}
}
来自 Windows CoreAudio API 的 COM 接口：
[ComImport]
[Guid( "BCDE0395-E52F-467C-8E3D-C4579291692E" )]
internal class MMDeviceEnumerator {
}
internal enum EDataFlow {
eRender,
eCapture,
eAll,
EDataFlow_enum_count
}
internal enum ERole {
eConsole,
eMultimedia,
eCommunications,
ERole_enum_count
}
[Guid( "A95664D2-9614-4F35-A746-DE8DB63617E6" ), InterfaceType( ComInterfaceType.InterfaceIsIUnknown )]
internal interface IMMDeviceEnumerator {
int NotImpl1();
[PreserveSig]
int GetDefaultAudioEndpoint( EDataFlow dataFlow, ERole role, out IMMDevice ppDevice );
// the rest is not implemented
}
[Guid( "D666063F-1587-4E43-81F1-B948E807363F" ), InterfaceType( ComInterfaceType.InterfaceIsIUnknown )]
internal interface IMMDevice {
[PreserveSig]
int Activate( ref Guid iid, int dwClsCtx, IntPtr pActivationParams, [MarshalAs( UnmanagedType.IUnknown )] out object ppInterface );
// the rest is not implemented
}
// http://netcoreaudio.codeplex.com/SourceControl/latest#trunk/Code/CoreAudio/Interfaces/IAudioEndpointVolume.cs
[Guid( "5CDF2C82-841E-4546-9722-0CF74078229A" ), InterfaceType( ComInterfaceType.InterfaceIsIUnknown )]
public interface IAudioEndpointVolume {
[PreserveSig]
int NotImpl1();
[PreserveSig]
int NotImpl2();
/// <summary>
/// Gets a count of the channels in the audio stream.
/// </summary>
/// <param name="channelCount">The number of channels.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetChannelCount(
[Out] [MarshalAs( UnmanagedType.U4 )] out UInt32 channelCount );
/// <summary>
/// Sets the master volume level of the audio stream, in decibels.
/// </summary>
/// <param name="level">The new master volume level in decibels.</param>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int SetMasterVolumeLevel(
[In] [MarshalAs( UnmanagedType.R4 )] float level,
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Sets the master volume level, expressed as a normalized, audio-tapered value.
/// </summary>
/// <param name="level">The new master volume level expressed as a normalized value between 0.0 and 1.0.</param>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int SetMasterVolumeLevelScalar(
[In] [MarshalAs( UnmanagedType.R4 )] float level,
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Gets the master volume level of the audio stream, in decibels.
/// </summary>
/// <param name="level">The volume level in decibels.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetMasterVolumeLevel(
[Out] [MarshalAs( UnmanagedType.R4 )] out float level );
/// <summary>
/// Gets the master volume level, expressed as a normalized, audio-tapered value.
/// </summary>
/// <param name="level">The volume level expressed as a normalized value between 0.0 and 1.0.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetMasterVolumeLevelScalar(
[Out] [MarshalAs( UnmanagedType.R4 )] out float level );
/// <summary>
/// Sets the volume level, in decibels, of the specified channel of the audio stream.
/// </summary>
/// <param name="channelNumber">The channel number.</param>
/// <param name="level">The new volume level in decibels.</param>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int SetChannelVolumeLevel(
[In] [MarshalAs( UnmanagedType.U4 )] UInt32 channelNumber,
[In] [MarshalAs( UnmanagedType.R4 )] float level,
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Sets the normalized, audio-tapered volume level of the specified channel in the audio stream.
/// </summary>
/// <param name="channelNumber">The channel number.</param>
/// <param name="level">The new master volume level expressed as a normalized value between 0.0 and 1.0.</param>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int SetChannelVolumeLevelScalar(
[In] [MarshalAs( UnmanagedType.U4 )] UInt32 channelNumber,
[In] [MarshalAs( UnmanagedType.R4 )] float level,
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Gets the volume level, in decibels, of the specified channel in the audio stream.
/// </summary>
/// <param name="channelNumber">The zero-based channel number.</param>
/// <param name="level">The volume level in decibels.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetChannelVolumeLevel(
[In] [MarshalAs( UnmanagedType.U4 )] UInt32 channelNumber,
[Out] [MarshalAs( UnmanagedType.R4 )] out float level );
/// <summary>
/// Gets the normalized, audio-tapered volume level of the specified channel of the audio stream.
/// </summary>
/// <param name="channelNumber">The zero-based channel number.</param>
/// <param name="level">The volume level expressed as a normalized value between 0.0 and 1.0.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetChannelVolumeLevelScalar(
[In] [MarshalAs( UnmanagedType.U4 )] UInt32 channelNumber,
[Out] [MarshalAs( UnmanagedType.R4 )] out float level );
/// <summary>
/// Sets the muting state of the audio stream.
/// </summary>
/// <param name="isMuted">True to mute the stream, or false to unmute the stream.</param>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int SetMute(
[In] [MarshalAs( UnmanagedType.Bool )] Boolean isMuted,
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Gets the muting state of the audio stream.
/// </summary>
/// <param name="isMuted">The muting state. True if the stream is muted, false otherwise.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetMute(
[Out] [MarshalAs( UnmanagedType.Bool )] out Boolean isMuted );
/// <summary>
/// Gets information about the current step in the volume range.
/// </summary>
/// <param name="step">The current zero-based step index.</param>
/// <param name="stepCount">The total number of steps in the volume range.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetVolumeStepInfo(
[Out] [MarshalAs( UnmanagedType.U4 )] out UInt32 step,
[Out] [MarshalAs( UnmanagedType.U4 )] out UInt32 stepCount );
/// <summary>
/// Increases the volume level by one step.
/// </summary>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int VolumeStepUp(
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Decreases the volume level by one step.
/// </summary>
/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int VolumeStepDown(
[In] [MarshalAs( UnmanagedType.LPStruct )] Guid eventContext );
/// <summary>
/// Queries the audio endpoint device for its hardware-supported functions.
/// </summary>
/// <param name="hardwareSupportMask">A hardware support mask that indicates the capabilities of the endpoint.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int QueryHardwareSupport(
[Out] [MarshalAs( UnmanagedType.U4 )] out UInt32 hardwareSupportMask );
/// <summary>
/// Gets the volume range of the audio stream, in decibels.
/// </summary>
/// <param name="volumeMin">The minimum volume level in decibels.</param>
/// <param name="volumeMax">The maximum volume level in decibels.</param>
/// <param name="volumeStep">The volume increment level in decibels.</param>
/// <returns>An HRESULT code indicating whether the operation passed of failed.</returns>
[PreserveSig]
int GetVolumeRange(
[Out] [MarshalAs( UnmanagedType.R4 )] out float volumeMin,
[Out] [MarshalAs( UnmanagedType.R4 )] out float volumeMax,
[Out] [MarshalAs( UnmanagedType.R4 )] out float volumeStep );
}