private static AudioDevice CreateDevice(NativeMethods.IMMDevice dev)
{
if (dev == null)
{
return(null);
}
string id;
Marshal.ThrowExceptionForHR(dev.GetId(out id));
Marshal.ThrowExceptionForHR(dev.GetState(out var state));
Dictionary <string, object> properties = new Dictionary <string, object>();
Marshal.ThrowExceptionForHR(dev.OpenPropertyStore(NativeMethods.STGM.READ, out var store));
if (store != null)
{
Marshal.ThrowExceptionForHR(store.GetCount(out var propCount));
for (int j = 0; j < propCount; j++)
{
NativeMethods.PROPERTYKEY pk;
if (store.GetAt(j, out pk) == 0)
{
NativeMethods.PROPVARIANT value = new NativeMethods.PROPVARIANT();
int errorCode = store.GetValue(ref pk, ref value);
if ((uint)errorCode == NativeMethods.ERROR_NO_SUCH_DEVINST)
{
continue;
}
Debug.Assert(errorCode == 0, "Error obtaining information from windows API - error code: " + errorCode);
object v = value.GetValue();
if (value.vt != NativeMethods.VARTYPE.VT_BLOB) // for some reason, this fails?
{
errorCode = NativeMethods.PropVariantClear(ref value);
Debug.Assert(errorCode == 0, "Error obtaining information from windows API - error code: " + errorCode);
}
string name = pk.ToString();
properties[name] = v;
}
}
}
return(new AudioDevice(id, (AudioDeviceStates)state, properties));
}
private static NativeMethods.IAudioSessionManager2 GetAudioSessionManager(NativeMethods.IMMDevice device)
{
if (device == null)
{
return(null);
}
// win7+ only
object o;
if (device.Activate(typeof(NativeMethods.IAudioSessionManager2).GUID, 0, IntPtr.Zero, out o) != 0 || o == null)
{
return(null);
}
return(o as NativeMethods.IAudioSessionManager2);
}
