I have an interesting situation where I need to do something like this:
[Export[typeof(ICandy1)]
[Export[typeof(ICandy2)]
public class Candy : ICandy2 { ... }
Where
public interface ICandy1 { ... }
public interface ICandy2 : ICandy1 { ... }
I could not find any messages on how to use multiple [Export] attributes, so I thought that hell could also try.
At first glance, it really worked. I have several methods that call both interfaces of a Candy instance, and everything was fine.
However, when I started testing the application, I saw that the behavior was wrong, and looking at the "Exit" window, I saw that I got a lot of COMExceptions. I could not track where they all came from, but they always arose when the working thread was asleep. Then I thought that it should be from the main thread, but did not know how to debug it at all. Nothing was supposed to happen in the GUI, and I disabled DispatchTimers just in case - the same thing.
Even stranger than COMExceptions was really, very erratic behavior when going through code. In about 30% of cases, when I take one step, it will jump out of the method, or it will be one step over two lines of code! It’s totally strange that I’m not used to seeing.
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COMException. , - -, , .
> UIAutomationProvider.dll!MS.Internal.Automation.UiaCoreProviderApi.UiaHostProviderFromHwnd(System.IntPtr hwnd) + 0x38 bytes
UIAutomationProvider.dll!System.Windows.Automation.Provider.AutomationInteropProvider.HostProviderFromHandle(System.IntPtr hwnd) + 0x2d bytes
PresentationCore.dll!MS.Internal.Automation.ElementProxy.HostRawElementProvider.get() + 0x65 bytes
[Native to Managed Transition]
[Managed to Native Transition]
UIAutomationProvider.dll!System.Windows.Automation.Provider.AutomationInteropProvider.RaiseAutomationPropertyChangedEvent(System.Windows.Automation.Provider.IRawElementProviderSimple element, System.Windows.Automation.AutomationPropertyChangedEventArgs e) + 0x2a bytes
PresentationCore.dll!System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() + 0x2c9 bytes
PresentationCore.dll!System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() + 0x2f8 bytes
PresentationCore.dll!System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() + 0x2f8 bytes
PresentationCore.dll!System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() + 0x2f8 bytes
PresentationCore.dll!System.Windows.ContextLayoutManager.fireAutomationEvents() + 0x98 bytes
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayout() + 0x65b bytes
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayoutCallback(object arg) + 0x19 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork() + 0x10 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks() + 0x97 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandlerCore(object resizedCompositionTarget = null) + 0x80 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandler(object resizedCompositionTarget) + 0x2b bytes
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate callback = {Method = Cannot evaluate expression because the code of the current method is optimized.}, object args = null, 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.DispatcherOperation.InvokeImpl() + 0x5d bytes
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(object state) + 0x38 bytes
mscorlib.dll!System.Threading.ExecutionContext.runTryCode(object userData) + 0x51 bytes
[Native to Managed Transition]
[Managed to Native Transition]
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x67 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x45 bytes
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.Invoke() + 0x63 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.ProcessQueue() + 0x127 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.WndProcHook(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled) + 0x63 bytes
WindowsBase.dll!MS.Win32.HwndWrapper.WndProc(System.IntPtr hwnd = 464158, int msg = 49869, System.IntPtr wParam = 0, System.IntPtr lParam = 0, 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 = Cannot evaluate expression because the code of the current method is optimized.}, 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 = 464158, int msg = 49869, System.IntPtr wParam = 0, System.IntPtr lParam = 0) + 0xdc bytes
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame frame = {System.Windows.Threading.DispatcherFrame}) + 0xc7 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrame(System.Windows.Threading.DispatcherFrame frame) + 0x49 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.Run() + 0x4c bytes
PresentationFramework.dll!System.Windows.Application.RunDispatcher(object ignore) + 0x1e bytes
PresentationFramework.dll!System.Windows.Application.RunInternal(System.Windows.Window window) + 0x6f bytes
PresentationFramework.dll!System.Windows.Application.Run(System.Windows.Window window) + 0x26 bytes
PresentationFramework.dll!System.Windows.Application.Run() + 0x19 bytes
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