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我創建了一個類，它來自System.Windows.Media.AudioSink以提供錄製功能。要檢查我的混凝土水槽的狀態我做了以下內容：檢查CaptureSource.State時出現InvalidOperationException
public class MyViewModel
{
private readonly MyAudioSink _myAudioSink; // this field is ensured in the ctor
public bool IsRecording
{
get
{
if (this._myAudioSink == null)
{
return false; // I know that `false` is wrong ...
}
return this._myAudioSink.CaptureSource.State == CaptureState.Started;
}
}
}
有時，當我詢問對proprety IsRecording，我得到以下異常：
{System.InvalidOperationException: Capture source is not stopped
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.SetValue(IManagedPeerBase obj, DependencyProperty property, DependencyObject doh)
at System.Windows.DependencyObject.SetValue(DependencyProperty property, DependencyObject doh)
at System.Windows.Media.CaptureSource..ctor()
at MS.Internal.CoreTypes.GetCoreWrapper(UInt32 typeId)
at MS.Internal.ManagedPeerTable.EnsureManagedPeer(IntPtr unmanagedPointer, Int32 typeIndex, Type type, Boolean preserveManagedObjectReference)
at MS.Internal.XcpImports.ConvertDO(IntPtr doPointer, Int32 typeIndex, Boolean releaseObjectReference)
at MS.Internal.XcpImports.ConvertType(CValue outVal, Int32 typeIndex, Boolean releaseObjectReference, Boolean deleteBuffer, IManagedPeerBase fromObject)
at MS.Internal.XcpImports.AudioSink_GetSource(AudioSink Sink)
at System.Windows.Media.AudioSink.get_CaptureSource()
at MyViewModel.get_IsRecording()
有時候，當我做this._myAudioSink.Stop()，我得到以下（類似）例外：
{System.InvalidOperationException: Capture source is not stopped
at MS.Internal.XcpImports.CheckHResult(UInt32 hr)
at MS.Internal.XcpImports.SetValue(IManagedPeerBase obj, DependencyProperty property, DependencyObject doh)
at System.Windows.DependencyObject.SetValue(DependencyProperty property, DependencyObject doh)
at System.Windows.Media.CaptureSource..ctor()
at MS.Internal.CoreTypes.GetCoreWrapper(UInt32 typeId)
at MS.Internal.ManagedPeerTable.EnsureManagedPeer(IntPtr unmanagedPointer, Int32 typeIndex, Type type, Boolean preserveManagedObjectReference)
at MS.Internal.XcpImports.ConvertDO(IntPtr doPointer, Int32 typeIndex, Boolean releaseObjectReference)
at MS.Internal.XcpImports.ConvertType(CValue outVal, Int32 typeIndex, Boolean releaseObjectReference, Boolean deleteBuffer, IManagedPeerBase fromObject)
at MS.Internal.XcpImports.AudioSink_GetSource(AudioSink Sink)
at System.Windows.Media.AudioSink.get_CaptureSource()
那麼...這是什麼原因？我怎樣才能防止這種異常（除了介紹我自己的領域，並將其設置在OnCaptureStarted和OnCaptureStopped的覆蓋範圍內）？
我在網上找到了這個問題的唯一話題就是here ......