/// <summary> /// Gets the control details /// </summary> protected void GetControlDetails() { mixerControlDetails.cbStruct = Marshal.SizeOf(mixerControlDetails); mixerControlDetails.dwControlID = mixerControl.dwControlID; if (IsCustom) { mixerControlDetails.cChannels = 0; } else if ((mixerControl.fdwControl & MixerInterop.MIXERCONTROL_CONTROLF_UNIFORM) != 0) { mixerControlDetails.cChannels = 1; } else { mixerControlDetails.cChannels = nChannels; } if ((mixerControl.fdwControl & MixerInterop.MIXERCONTROL_CONTROLF_MULTIPLE) != 0) { mixerControlDetails.hwndOwner = (IntPtr)mixerControl.cMultipleItems; } else if (IsCustom) { mixerControlDetails.hwndOwner = IntPtr.Zero; // TODO: special cases } else { mixerControlDetails.hwndOwner = IntPtr.Zero; } if (IsBoolean) { mixerControlDetails.cbDetails = Marshal.SizeOf(new MixerInterop.MIXERCONTROLDETAILS_BOOLEAN()); } else if (IsListText) { mixerControlDetails.cbDetails = Marshal.SizeOf(new MixerInterop.MIXERCONTROLDETAILS_LISTTEXT()); } else if (IsSigned) { mixerControlDetails.cbDetails = Marshal.SizeOf(new MixerInterop.MIXERCONTROLDETAILS_SIGNED()); } else if (IsUnsigned) { mixerControlDetails.cbDetails = Marshal.SizeOf(new MixerInterop.MIXERCONTROLDETAILS_UNSIGNED()); } else { // must be custom mixerControlDetails.cbDetails = mixerControl.Metrics.customData; } var detailsSize = mixerControlDetails.cbDetails * mixerControlDetails.cChannels; if ((mixerControl.fdwControl & MixerInterop.MIXERCONTROL_CONTROLF_MULTIPLE) != 0) { // fixing issue 16390 - calculating size correctly for multiple items detailsSize *= (int)mixerControl.cMultipleItems; } IntPtr buffer = Marshal.AllocCoTaskMem(detailsSize); // To copy stuff in: // Marshal.StructureToPtr( theStruct, buffer, false ); mixerControlDetails.paDetails = buffer; MmResult err = MixerInterop.mixerGetControlDetails(mixerHandle, ref mixerControlDetails, MixerFlags.Value | mixerHandleType); // let the derived classes get the details before we free the handle if (err == MmResult.NoError) { GetDetails(mixerControlDetails.paDetails); } Marshal.FreeCoTaskMem(buffer); if (err != MmResult.NoError) { throw new MmException(err, "mixerGetControlDetails"); } }