我正在尝试更改某个进程的音量，我必须在字符串中定义应用程序的名称。但是我可以改变音量的唯一过程就是Mozilla Firefox。我将添加一些代码作为解释;
Audio.cs
namespace KJKerstborrel
{
[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
}
[Guid("77AA99A0-1BD6-484F-8BC7-2C654C9A9B6F"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IAudioSessionManager2
{
int NotImpl1();
int NotImpl2();
[PreserveSig]
int GetSessionEnumerator(out IAudioSessionEnumerator SessionEnum);
// the rest is not implemented
}
[Guid("E2F5BB11-0570-40CA-ACDD-3AA01277DEE8"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IAudioSessionEnumerator
{
[PreserveSig]
int GetCount(out int SessionCount);
[PreserveSig]
int GetSession(int SessionCount, out IAudioSessionControl Session);
}
[Guid("F4B1A599-7266-4319-A8CA-E70ACB11E8CD"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IAudioSessionControl
{
int NotImpl1();
[PreserveSig]
int GetDisplayName([MarshalAs(UnmanagedType.LPWStr)] out string pRetVal);
// the rest is not implemented
}
[Guid("87CE5498-68D6-44E5-9215-6DA47EF883D8"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface ISimpleAudioVolume
{
[PreserveSig]
int SetMasterVolume(float fLevel, ref Guid EventContext);
[PreserveSig]
int GetMasterVolume(out float pfLevel);
[PreserveSig]
int SetMute(bool bMute, ref Guid EventContext);
[PreserveSig]
int GetMute(out bool pbMute);
}
static class Audio
{
public static void SetVolume(string app, int volume)
{
foreach (string name in Audio.EnumerateApplications())
{
Console.WriteLine("name:" + name);
if (name.Equals(app, StringComparison.OrdinalIgnoreCase))
{
// display mute state & volume level (% of master)
Console.WriteLine("Mute:" + Audio.GetApplicationMute(app));
Console.WriteLine("Volume:" + Audio.GetApplicationVolume(app));
// set the volume to half of master volume (50%)
Audio.SetApplicationVolume(app, volume);
}
}
}
public static float? GetApplicationVolume(string name)
{
ISimpleAudioVolume volume = GetVolumeObject(name);
if (volume == null)
return null;
float level;
volume.GetMasterVolume(out level);
return level * 100;
}
public static bool? GetApplicationMute(string name)
{
ISimpleAudioVolume volume = GetVolumeObject(name);
if (volume == null)
return null;
bool mute;
volume.GetMute(out mute);
return mute;
}
public static void SetApplicationVolume(string name, float level)
{
ISimpleAudioVolume volume = GetVolumeObject(name);
if (volume == null)
return;
Guid guid = Guid.Empty;
volume.SetMasterVolume(level / 100, ref guid);
}
public static void SetApplicationMute(string name, bool mute)
{
ISimpleAudioVolume volume = GetVolumeObject(name);
if (volume == null)
return;
Guid guid = Guid.Empty;
volume.SetMute(mute, ref guid);
}
public static IEnumerable<string> EnumerateApplications()
{
// get the speakers (1st render + multimedia) device
IMMDeviceEnumerator deviceEnumerator = (IMMDeviceEnumerator)(new MMDeviceEnumerator());
IMMDevice speakers;
deviceEnumerator.GetDefaultAudioEndpoint(EDataFlow.eRender, ERole.eMultimedia, out speakers);
// activate the session manager. we need the enumerator
Guid IID_IAudioSessionManager2 = typeof(IAudioSessionManager2).GUID;
object o;
speakers.Activate(ref IID_IAudioSessionManager2, 0, IntPtr.Zero, out o);
IAudioSessionManager2 mgr = (IAudioSessionManager2)o;
// enumerate sessions for on this device
IAudioSessionEnumerator sessionEnumerator;
mgr.GetSessionEnumerator(out sessionEnumerator);
int count;
sessionEnumerator.GetCount(out count);
for (int i = 0; i < count; i++)
{
IAudioSessionControl ctl;
sessionEnumerator.GetSession(i, out ctl);
string dn;
ctl.GetDisplayName(out dn);
yield return dn;
Marshal.ReleaseComObject(ctl);
}
Marshal.ReleaseComObject(sessionEnumerator);
Marshal.ReleaseComObject(mgr);
Marshal.ReleaseComObject(speakers);
Marshal.ReleaseComObject(deviceEnumerator);
}
private static ISimpleAudioVolume GetVolumeObject(string name)
{
// get the speakers (1st render + multimedia) device
IMMDeviceEnumerator deviceEnumerator = (IMMDeviceEnumerator)(new MMDeviceEnumerator());
IMMDevice speakers;
deviceEnumerator.GetDefaultAudioEndpoint(EDataFlow.eRender, ERole.eMultimedia, out speakers);
// activate the session manager. we need the enumerator
Guid IID_IAudioSessionManager2 = typeof(IAudioSessionManager2).GUID;
object o;
speakers.Activate(ref IID_IAudioSessionManager2, 0, IntPtr.Zero, out o);
IAudioSessionManager2 mgr = (IAudioSessionManager2)o;
// enumerate sessions for on this device
IAudioSessionEnumerator sessionEnumerator;
mgr.GetSessionEnumerator(out sessionEnumerator);
int count;
sessionEnumerator.GetCount(out count);
// search for an audio session with the required name
// NOTE: we could also use the process id instead of the app name (with IAudioSessionControl2)
ISimpleAudioVolume volumeControl = null;
for (int i = 0; i < count; i++)
{
IAudioSessionControl ctl;
sessionEnumerator.GetSession(i, out ctl);
string dn;
ctl.GetDisplayName(out dn);
if (string.Compare(name, dn, StringComparison.OrdinalIgnoreCase) == 0)
{
volumeControl = ctl as ISimpleAudioVolume;
break;
}
Marshal.ReleaseComObject(ctl);
}
Marshal.ReleaseComObject(sessionEnumerator);
Marshal.ReleaseComObject(mgr);
Marshal.ReleaseComObject(speakers);
Marshal.ReleaseComObject(deviceEnumerator);
return volumeControl;
}
}
}
我在FormMain中调用变量
const string APP = "Mozilla Firefox";
上面的一个有效，但是这样的事情没有;
const string APP = "Spotify";
我猜它在我的代码中发布了GUID，但我似乎无法找到答案。
答案 0 :(得分：0)
如果您尝试与流程名称匹配，则firefox适用于Mozilla Firefox。在这种情况下，您可以使用String.Contains()进行搜索。
答案 1 :(得分：0)
似乎为了让您的进程显示在系统托盘Volume Mixer中，它必须首先发出声音。可能还有另一种方式。
无论如何，这是一个播放空声的片段：
// wave signature for no sound
byte[] arr = new byte[] { 82, 73, 70, 70, 36, 0, 0, 0, 87, 65, 86, 69, 102, 109, 116, 32, 16, 0, 0, 0, 1, 0, 2, 0, 68, 172, 0, 0, 16, 177, 2, 0, 4, 0, 16, 0, 100, 97, 116, 97, 0, 0, 0, 0};
using (MemoryStream ms = new MemoryStream()) {
ms.Write(arr);
ms.Position = 0;
using (SoundPlayer p = new SoundPlayer(ms)) {
p.Play();
}
}
关于波浪生成的更深入讨论可以是found here。
字节数组是使用上面链接中的示例创建的，只有页眉和页脚。
在卷混音器中完成进程后，您应该按进程ID而不是按名称检索其卷控制对象。因此，如果Spotify.exe是您自己的进程，那么您可以使用：
Process.GetCurrentProcess().Id
Anders Keller Carstensen在此发布了一个解决方案：Controlling Application's Volume: By Process-ID