Trace.Assert 没有中断，也不显示消息框

Question

我有一个 WPF 应用程序，我在其中在画布上移动数据。 当我像怪物一样尝试用鼠标移动数据时，问题就开始了。

以下是操作的顺序：

• 画布上的 MouseMove 被触发
• 在 MouseMove 中，我更改了一些数据
• Trace.Assert 失败。调试器不会中断，消息框也不会
• 中断另一个 MouseMove 被触发
• 数据再次更改
• 由于集合中的重入检查而引发异常。调试器在那里中断。断言消息框从未显示。

这里的大问题是我可以回到断言，但它不是断言失败时的数据，而是最后修改的数据......所以基本上我无法正确调试。

这是从第一个 MouseMove 开始的堆栈跟踪（注意 ShowMessageBoxAssert 以及它仍在继续的事实...）：

  .Models.FCurve.MoveKey(int keyIndex = 3, double keyTime = 1182.0) Line 199 C#
  .Models.FCurve.KeyTimeChanged(Models.FCurveKey timeChangeKey = {Models.FCurveKey}) Line 186 + 0x2d bytes C#
  .Models.FCurve.AddKeyToArray.AnonymousMethod(object sender = {Models.FCurveKey}, System.EventArgs args = {System.EventArgs}) Line 163 + 0x11 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  .Models.FCurveKey.OnTimeChanged() Line 45 + 0x14 bytes C#
  .Models.FCurveKey..ctor.AnonymousMethod(object sender = {FCurveEditorTestApp.Impl.FCurveKeyImpl}, System.EventArgs args = {System.EventArgs}) Line 18 + 0x8 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  FCurveEditorTestApp.exe!FCurveEditorTestApp.Impl.FCurveKeyImpl.OnTimeChanged() Line 43 + 0x14 bytes C#
  FCurveEditorTestApp.exe!FCurveEditorTestApp.Impl.FCurveKeyImpl.Time.set(double value = 1182.0) Line 34 + 0x8 bytes C#
  .Models.FCurveKey.Time.set(double value = 1182.0) Line 36 + 0x1b bytes C#
  .ViewModels.CurveKeyViewModel.X.set(double value = 1182.0) Line 32 + 0x2b bytes C#
  .ViewModels.CurveAreaViewModel.MoveSelectedItem.AnonymousMethod(ViewModels.CurveKeyViewModel key = {ViewModels.CurveKeyViewModel}) Line 127 + 0x2d bytes C#
  Collections.CollectionHelper.ForEach(System.Collections.Generic.IEnumerable source = {System.Linq.Enumerable.OfTypeIterator}, System.Action action = {Method = {Void b__8(ViewModels.CurveKeyViewModel)}}) Line 31 + 0xe bytes C#
  .ViewModels.CurveAreaViewModel.MoveSelectedItem(double deltaX = 693.0, double deltaY = 35.0) Line 126 + 0x63 bytes C#
  .Views.CurveAreaView._AreaCanvas_MouseMove(object sender = {System.Windows.Controls.Canvas}, System.Windows.Input.MouseEventArgs e = {System.Windows.Input.MouseEventArgs}) Line 195 + 0x2d bytes C#
  PresentationCore.dll!System.Windows.Input.MouseEventArgs.InvokeEventHandler(System.Delegate genericHandler, object genericTarget) + 0x34 bytes 
  PresentationCore.dll!System.Windows.RoutedEventArgs.InvokeHandler(System.Delegate handler, object target) + 0x27 bytes 
  PresentationCore.dll!System.Windows.RoutedEventHandlerInfo.InvokeHandler(object target, System.Windows.RoutedEventArgs routedEventArgs) + 0x3e bytes 
  PresentationCore.dll!System.Windows.EventRoute.InvokeHandlersImpl(object source = {System.Windows.Controls.Canvas}, System.Windows.RoutedEventArgs args = {System.Windows.Input.MouseEventArgs}, bool reRaised = false) + 0x1bf bytes 
  PresentationCore.dll!System.Windows.UIElement.RaiseEventImpl(System.Windows.DependencyObject sender = {System.Windows.Controls.Canvas}, System.Windows.RoutedEventArgs args = {System.Windows.Input.MouseEventArgs}) + 0x79 bytes 
  PresentationCore.dll!System.Windows.UIElement.RaiseEvent(System.Windows.RoutedEventArgs args = {System.Windows.Input.MouseEventArgs}, bool trusted) + 0x35 bytes 
  PresentationCore.dll!System.Windows.Input.InputManager.ProcessStagingArea() + 0x311 bytes 
  PresentationCore.dll!System.Windows.Input.InputManager.ProcessInput(System.Windows.Input.InputEventArgs input) + 0x42 bytes 
  PresentationCore.dll!System.Windows.Input.InputProviderSite.ReportInput(System.Windows.Input.InputReport inputReport) + 0x62 bytes 
  PresentationCore.dll!System.Windows.Interop.HwndMouseInputProvider.ReportInput(System.IntPtr hwnd, System.Windows.Input.InputMode mode, int timestamp, System.Windows.Input.RawMouseActions actions, int x, int y, int wheel) + 0x2e2 bytes 
  PresentationCore.dll!System.Windows.Interop.HwndMouseInputProvider.FilterMessage(System.IntPtr hwnd = 2628604, int msg = 512, System.IntPtr wParam = 1, System.IntPtr lParam = 30409804, ref bool handled = false) + 0x22b bytes 
  PresentationCore.dll!System.Windows.Interop.HwndSource.InputFilterMessage(System.IntPtr hwnd = 2628604, int msg = 512, System.IntPtr wParam = 1, System.IntPtr lParam = 30409804, ref bool handled = false) + 0x75 bytes 
  WindowsBase.dll!MS.Win32.HwndWrapper.WndProc(System.IntPtr hwnd = 2628604, int msg = 512, System.IntPtr wParam = 1, System.IntPtr lParam = 30409804, ref bool handled = false) + 0xbe bytes 
  WindowsBase.dll!MS.Win32.HwndSubclass.DispatcherCallbackOperation(object o) + 0x7a bytes 
  WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate callback = {Method = {System.Object DispatcherCallbackOperation(System.Object)}}, object args = {MS.Win32.HwndSubclass.DispatcherOperationCallbackParameter}, bool isSingleParameter = true) + 0x8a bytes 
  WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.TryCatchWhen(object source = {System.Windows.Threading.Dispatcher}, System.Delegate callback, object args, bool isSingleParameter, System.Delegate catchHandler = null) + 0x4a bytes 
  WindowsBase.dll!System.Windows.Threading.Dispatcher.WrappedInvoke(System.Delegate callback, object args, bool isSingleParameter, System.Delegate catchHandler) + 0x44 bytes 
  WindowsBase.dll!System.Windows.Threading.Dispatcher.InvokeImpl(System.Windows.Threading.DispatcherPriority priority, System.TimeSpan timeout, System.Delegate method, object args, bool isSingleParameter) + 0x91 bytes 
  WindowsBase.dll!System.Windows.Threading.Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority priority, System.Delegate method, object arg) + 0x40 bytes 
  WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr hwnd = 2628604, int msg = 512, System.IntPtr wParam = 1, System.IntPtr lParam = 30409804) + 0xdc bytes 
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  System.dll!System.Diagnostics.AssertWrapper.ShowMessageBoxAssert(string stackTrace, string message, string detailMessage) + 0x103 bytes 
  System.dll!System.Diagnostics.DefaultTraceListener.Fail(string message, string detailMessage) + 0xb2 bytes 
  System.dll!System.Diagnostics.DefaultTraceListener.Fail(string message) + 0xa bytes 
  System.dll!System.Diagnostics.TraceInternal.Fail(string message = "") + 0xb6 bytes 
  System.dll!System.Diagnostics.Trace.Assert(bool condition) + 0x1c bytes 
  .ViewModels.CurvePathViewModel.CurvePathViewModel(Models.FCurveKey startKey = {Models.FCurveKey}, Models.FCurveKey endKey = {Models.FCurveKey}, ViewModels.IInterpolationProvider interpolatorProvider = {ViewModels.InterpolationInfoProvider}) Line 29 + 0x4e bytes C#
  .ViewModels.CurvePathViewModel.CurvePathViewModel(ViewModels.CurveKeyViewModel startKey = {ViewModels.CurveKeyViewModel}, ViewModels.CurveKeyViewModel endKey = {ViewModels.CurveKeyViewModel}, ViewModels.IInterpolationProvider interpolatorProvider = {ViewModels.InterpolationInfoProvider}) Line 20 + 0x81 bytes C#
  .ViewModels.CurveViewModel.UpdateSegmentForKey(ViewModels.CurveKeyViewModel key = {ViewModels.CurveKeyViewModel}) Line 215 + 0x41 bytes C#
  .ViewModels.CurveViewModel.KeyViewModelsChanged(object sender = Count = 13, System.Collections.Specialized.NotifyCollectionChangedEventArgs e = {System.Collections.Specialized.NotifyCollectionChangedEventArgs}) Line 187 + 0x30 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs e) + 0x50 bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedAction action, object item, int index, int oldIndex) + 0x34 bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.MoveItem(int oldIndex, int newIndex) + 0x6f bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.Move(int oldIndex, int newIndex) + 0xe bytes 
  Collections.CollectionSynchronizer._SourceList_CollectionChanged(object sender = Count = 13, System.Collections.Specialized.NotifyCollectionChangedEventArgs e = {System.Collections.Specialized.NotifyCollectionChangedEventArgs}) Line 239 + 0x45 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  WindowsBase.dll!System.Collections.ObjectModel.ReadOnlyObservableCollection.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs args) + 0x1d bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ReadOnlyObservableCollection.HandleCollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) + 0xe bytes 
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedEventArgs e) + 0x50 bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.OnCollectionChanged(System.Collections.Specialized.NotifyCollectionChangedAction action, object item, int index, int oldIndex) + 0x34 bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.MoveItem(int oldIndex, int newIndex) + 0x6f bytes 
  WindowsBase.dll!System.Collections.ObjectModel.ObservableCollection.Move(int oldIndex, int newIndex) + 0xe bytes 
  .Models.FCurve.MoveKey(int keyIndex = 1, double keyTime = 489.0) Line 199 + 0x19 bytes C#
  .Models.FCurve.KeyTimeChanged(Models.FCurveKey timeChangeKey = {Models.FCurveKey}) Line 186 + 0x2d bytes C#
  .Models.FCurve.AddKeyToArray.AnonymousMethod(object sender = {Models.FCurveKey}, System.EventArgs args = {System.EventArgs}) Line 163 + 0x11 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  .Models.FCurveKey.OnTimeChanged() Line 45 + 0x14 bytes C#
  .Models.FCurveKey..ctor.AnonymousMethod(object sender = {FCurveEditorTestApp.Impl.FCurveKeyImpl}, System.EventArgs args = {System.EventArgs}) Line 18 + 0x8 bytes C#
  [Native to Managed Transition] 
  [Managed to Native Transition] 
  FCurveEditorTestApp.exe!FCurveEditorTestApp.Impl.FCurveKeyImpl.OnTimeChanged() Line 43 + 0x14 bytes C#
  FCurveEditorTestApp.exe!FCurveEditorTestApp.Impl.FCurveKeyImpl.Time.set(double value = 489.0) Line 34 + 0x8 bytes C#
  .Models.FCurveKey.Time.set(double value = 489.0) Line 36 + 0x1b bytes C#
  .ViewModels.CurveKeyViewModel.X.set(double value = 489.0) Line 32 + 0x2b bytes C#
  .ViewModels.CurveAreaViewModel.MoveSelectedItem.AnonymousMethod(ViewModels.CurveKeyViewModel key = {ViewModels.CurveKeyViewModel}) Line 127 + 0x2d bytes C#
  Collections.CollectionHelper.ForEach(System.Collections.Generic.IEnumerable source = {System.Linq.Enumerable.OfTypeIterator}, System.Action action = {Method = {Void b__8(ViewModels.CurveKeyViewModel)}}) Line 31 + 0xe bytes C#
  .ViewModels.CurveAreaViewModel.MoveSelectedItem(double deltaX = 82.0, double deltaY = -9.0) Line 126 + 0x63 bytes C#
  Views.CurveAreaView._AreaCanvas_MouseMove(object sender = {System.Windows.Controls.Canvas}, System.Windows.Input.MouseEventArgs e = {System.Windows.Input.MouseEventArgs}) Line 195 + 0x2d bytes C#

问题是：为什么会发生这种情况，以及我应该做什么才能使其在断言时中断？

我想过使用异常，也许是为了调试，但这确实是我需要的断言。我也在考虑所有其他断言，而不需要总是将它们转换为异常以进行调试......

Answer 1

您可以通过编写自己的 TraceListener 在 AppDomain 范围内（如果您的应用程序只有一个 AppDomain，则在应用程序范围内）执行此操作。

首先创建一个包含 ExceptionTraceListener 类的类库项目 MyTraceListeners.dll：

public class ExceptionTraceListener : TraceListener
{
  public override void Write(string message)
  {
    // Do nothing
  }
  public override void Fail(string message)
  {
    Debugger.Break();  // or if you prefer, throw new Exception(...)
  }
  public override void Fail(string message, string detailMessage)
  {
    Debugger.Break();  // or if you prefer, throw new Exception(...)
  }
}

现在您可以在应用程序的 .config< 中注册此 TraceListener /code> 文件以通常的方式：

<configuration>
  ...
  <system.diagnostics>
    ...
    <trace>
      <listeners>
        <clear />
        <add name="myListener" type="ExceptionTraceListener, MyTraceListeners" />
      </listeners>
    </trace>
  </system.diagnostics>
</configuration>

当您使用这些 .config 文件条目运行应用程序时，调试器将在每次断言失败时立即中断。

另请注意此配置文件中的 ，以清除 Machine.config 中列出的任何默认 TraceListeners。这很重要，因为默认的 TraceListener 将在您之前收到调用，并且仍然弹出 MessageBox。

Answer 2

我以前见过类似的东西，当时有效的解决方法是添加一个 if 语句，其条件与断言相同，但被否定，并与调试器中在 if 的 then 块中的语句上设置的断点相结合。