PresentationFramework에서 NullReferenceException을 디버깅하는 방법은 무엇입니까?

Question

내 .NET 4 응용 프로그램은 WPF TreeView를 사용하여 키보드 탐색 및 지연로드를 활성화합니다. 내 문제은 매우 드물지만 아래에 표시된 예외가 발생합니다. 이 문제는 개발 개월 동안 한 번만 나에게 일어 났고, 나는 한동안 이것을 얻은 여러 고객의 버그 보고서를 가지고 있습니다. 너무나 희귀해서 뭔가를 바꿀 수없고 잠시 동안 앱을 가지고 놀고 문제가 사라 졌는지 알 수 없습니다.

그러나 내 주 질문이입니다 : 스택 추적은 Microsoft 코드 만 보여 주며 거기에는 나와 아무 것도 없습니다. 이것은 .NET/WPF의 버그입니까? 근본 원인에 도달 할 수있는 기회가 있습니까?

Type: System.NullReferenceException 
Message: Object reference not set to an instance of an object. 
Source: PresentationFramework 
Stack trace: at System.Windows.Controls.ItemContainerGenerator.ContainerFromIndex(Int32 index) 
    at System.Windows.Controls.TreeViewItem.FindNextFocusableItem(Boolean walkIntoSubtree) 
    at System.Windows.Controls.TreeViewItem.InternalPredictFocus(FocusNavigationDirection direction) 
    at System.Windows.Controls.VirtualizingStackPanel.FocusChanged(KeyboardFocusChangedEventArgs e) 
    at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) 
    at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) 
    at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) 
    at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args) 
    at System.Windows.Input.InputManager.ProcessStagingArea() 
    at System.Windows.Input.KeyboardDevice.ChangeFocus(DependencyObject focus, Int32 timestamp) 
    at System.Windows.Input.KeyboardDevice.Focus(DependencyObject focus, Boolean askOld, Boolean askNew, Boolean forceToNullIfFailed) 
    at System.Windows.Input.KeyboardDevice.Focus(IInputElement element) 
    at System.Windows.UIElement.Focus() 
    at System.Windows.Controls.TreeViewItem.OnItemsChanged(NotifyCollectionChangedEventArgs e) 
    at System.Windows.Controls.ItemsControl.OnItemCollectionChanged(Object sender, NotifyCollectionChangedEventArgs e) 
    at System.Collections.Specialized.NotifyCollectionChangedEventHandler.Invoke(Object sender, NotifyCollectionChangedEventArgs e) 
    at System.Windows.Data.CollectionView.OnCollectionChanged(NotifyCollectionChangedEventArgs args) 
    at System.Windows.Controls.ItemCollection.SetCollectionView(CollectionView view) 
    at System.Windows.Controls.ItemsControl.OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) 
    at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e) 
    at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e) 
    at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args) 
    at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType) 
    at System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange) 
    at System.Windows.Data.BindingExpression.Activate(Object item) 
    at System.Windows.Data.BindingExpression.OnDataContextChanged(DependencyObject contextElement) 
    at System.Windows.Data.BindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args) 
    at System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args) 
    at System.Windows.Data.BindingExpression.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args) 
    at System.Windows.DependentList.InvalidateDependents(DependencyObject source, DependencyPropertyChangedEventArgs sourceArgs) 
    at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args) 
    at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType) 
    at System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal) 
    at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value) 
    at System.Windows.Controls.ItemContainerGenerator.System.Windows.Controls.Primitives.IItemContainerGenerator.RemoveAll() 
    at System.Windows.Controls.VirtualizingStackPanel.ClearAllContainers(ItemsControl itemsControl) 
    at System.Windows.Controls.ItemsControl.MS.Internal.Controls.IGeneratorHost.ClearContainerForItem(DependencyObject container, Object item) 
    at System.Windows.Controls.ItemContainerGenerator.UnlinkContainerFromItem(DependencyObject container, Object item) 
    at System.Windows.Controls.ItemContainerGenerator.Remove(GeneratorPosition position, Int32 count, Boolean isRecycling) 
    at System.Windows.Controls.VirtualizingStackPanel.CleanupRange(IList children, IItemContainerGenerator generator, Int32 startIndex, Int32 count) 
    at System.Windows.Controls.VirtualizingStackPanel.CleanupContainers(Int32 firstViewport, ItemsControl itemsControl) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.TreeViewItem.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.TreeViewItem.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.TreeViewItem.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.TreeViewItem.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.TreeViewItem.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ItemsPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ScrollContentPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.ScrollViewer.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Border.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Control.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) 
    at System.Windows.Controls.Grid.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) 
    at System.Windows.Controls.ContentPresenter.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Border.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.Controls.Control.MeasureOverride(Size constraint) 
    at System.Windows.FrameworkElement.MeasureCore(Size availableSize) 
    at System.Windows.UIElement.Measure(Size availableSize) 
    at System.Windows.ContextLayoutManager.UpdateLayout() 
    at System.Windows.Interop.HwndSource.Process_WM_SIZE(UIElement rootUIElement, IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam) 
    at System.Windows.Interop.HwndSource.LayoutFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) 
    at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) 
    at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) 
    at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) 
    at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler) 
Target: System.Windows.DependencyObject ContainerFromIndex(Int32) 
Inner exception message: 

참고 :이 컴퓨터에는 완전히 패치 된 Windows 7 x64가 실행됩니다.

Answer 1

나는 개인적으로 WPF에서 버그를 발견하지 못했습니다. 그러나 WPF 코드를 실행하면 자주 문제의 출처를 직접 추적 할 수있게되었습니다. 여기

디버깅 프레임 워크 소스를 사용하도록 설정하는 방법에 대한 몇 가지 MSDN 기사입니다 : 모든 버전에

• Visual Studio 2008 version
• Visual Studio 2010 version

링크 : https://msdn.microsoft.com/en-us/library/cc667410.aspx