C# 在绑定的listbox中禁用对listboxitem的拖放；集合被修改为异常

我有一个WPF列表框，它的ItemSource绑定到一个集合。当用户单击所选项目并将其拖到列表框中的下一个项目上时，有时会出现无效操作异常：“集合已修改；枚举操作可能无法执行”

我尝试将ItemContainerStyle上的AllowDrop设置为false，并使用

e.Handled=true处理PreviewDragEnter/Leave但我仍然可以得到崩溃

有没有办法真正阻止这种行为？我不需要移动列表框项目

以下是我的WPF列表框代码：

    <ListBox ItemsSource="{Binding Conversations}"
             SelectedItem="{Binding SelectedConversation}"
             VirtualizingStackPanel.IsVirtualizing="True"
             PreviewDragEnter="UIElement_OnPreviewDragEnter">
       <ListBox.ItemContainerStyle>
          <Style BasedOn="{StaticResource MyListBoxItemStyle}" TargetType="{x:Type ListBoxItem}">
             <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
             <Setter Property="AllowDrop" Value="False"/>
             <EventSetter Event="PreviewDragEnter" Handler="UIElement_OnPreviewDragEnter" />
             <EventSetter Event="PreviewDragLeave" Handler="UIElement_OnPreviewDragEnter"/>
             <EventSetter Event="MouseEnter" Handler="EventSetter_OnHandler"></EventSetter>
          </Style>
       </ListBox.ItemContainerStyle>
    </ListBox>

这是异常消息

Current_DispatcherUnhandledException : System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
   at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
   at System.Collections.Generic.List`1.Enumerator.MoveNextRare()
   at System.Collections.Generic.List`1.Enumerator.MoveNext()
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.CreateDeltaSelectionChange(List`1 unselectedItems, List`1 selectedItems)
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.End()
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.SelectJustThisItem(ItemInfo info, Boolean assumeInItemsCollection)
   at System.Windows.Controls.ListBox.MakeSingleSelection(ListBoxItem listItem)
   at System.Windows.Controls.ListBox.MakeKeyboardSelection(ListBoxItem item)
   at System.Windows.Controls.ListBox.FocusItem(ItemInfo info, ItemNavigateArgs itemNavigateArgs)
   at System.Windows.Controls.ItemsControl.NavigateToItem(Object item, Int32 elementIndex, ItemNavigateArgs itemNavigateArgs, Boolean alwaysAtTopOfViewport)
   at System.Windows.Controls.ListBox.NotifyListItemMouseDragged(ListBoxItem listItem)
   at System.Windows.Controls.ListBoxItem.OnMouseEnter(MouseEventArgs e)
   at System.Windows.UIElement.OnMouseEnterThunk(Object sender, MouseEventArgs e)
   at System.Windows.Input.MouseEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
   at System.Windows.MouseOverProperty.FireNotifications(UIElement uie, ContentElement ce, UIElement3D uie3D, Boolean oldValue)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.OnOriginValueChanged(DependencyObject oldOrigin, DependencyObject newOrigin, IList`1 otherOrigins, DeferredElementTreeState& oldTreeState, Action`2 originChangedAction)
   at System.Windows.Input.MouseDevice.ChangeMouseOver(IInputElement mouseOver, Int32 timestamp)
   at System.Windows.Input.MouseDevice.PreNotifyInput(Object sender, NotifyInputEventArgs e)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
   at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at System.Windows.Interop.HwndSource.InputFilterMessage(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)

这很可能是因为在
对话
上有一个
foreach
循环或另一个
IEnumerable
操作，在移动列表框项目时执行

尝试同步访问
对话
似乎是将IsSelected绑定到我的模型导致了问题。删除绑定修复了它，不会影响UI。
我很确定我没有进行任何迭代。我在所有for循环中都设置了一个断点，没有一个被命中。拖动列表框项是否会固有地重新排列集合？如果是这种情况，我如何停止所有拖动行为？我有相同的错误，这确实是由于绑定了两个：
ListBox.SelectedItem
和
ListBoxItem.IsSelected
。在我的例子中，问题是由IsSynchronizedWithCurrentItem=“True”

引起的，删除它就足够了。虽然有2个绑定（由于团队长期开发而出现）显然是不必要的，因为

IsSelected

（当项目具有此属性时使用）更优越。

Current_DispatcherUnhandledException : System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
   at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
   at System.Collections.Generic.List`1.Enumerator.MoveNextRare()
   at System.Collections.Generic.List`1.Enumerator.MoveNext()
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.CreateDeltaSelectionChange(List`1 unselectedItems, List`1 selectedItems)
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.End()
   at System.Windows.Controls.Primitives.Selector.SelectionChanger.SelectJustThisItem(ItemInfo info, Boolean assumeInItemsCollection)
   at System.Windows.Controls.ListBox.MakeSingleSelection(ListBoxItem listItem)
   at System.Windows.Controls.ListBox.MakeKeyboardSelection(ListBoxItem item)
   at System.Windows.Controls.ListBox.FocusItem(ItemInfo info, ItemNavigateArgs itemNavigateArgs)
   at System.Windows.Controls.ItemsControl.NavigateToItem(Object item, Int32 elementIndex, ItemNavigateArgs itemNavigateArgs, Boolean alwaysAtTopOfViewport)
   at System.Windows.Controls.ListBox.NotifyListItemMouseDragged(ListBoxItem listItem)
   at System.Windows.Controls.ListBoxItem.OnMouseEnter(MouseEventArgs e)
   at System.Windows.UIElement.OnMouseEnterThunk(Object sender, MouseEventArgs e)
   at System.Windows.Input.MouseEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
   at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
   at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
   at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
   at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
   at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
   at System.Windows.MouseOverProperty.FireNotifications(UIElement uie, ContentElement ce, UIElement3D uie3D, Boolean oldValue)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.FirePropertyChangeInAncestry(DependencyObject element, Boolean oldValue, DeferredElementTreeState treeState, Action`2 originChangedAction)
   at System.Windows.ReverseInheritProperty.OnOriginValueChanged(DependencyObject oldOrigin, DependencyObject newOrigin, IList`1 otherOrigins, DeferredElementTreeState& oldTreeState, Action`2 originChangedAction)
   at System.Windows.Input.MouseDevice.ChangeMouseOver(IInputElement mouseOver, Int32 timestamp)
   at System.Windows.Input.MouseDevice.PreNotifyInput(Object sender, NotifyInputEventArgs e)
   at System.Windows.Input.InputManager.ProcessStagingArea()
   at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
   at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
   at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
   at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at System.Windows.Interop.HwndSource.InputFilterMessage(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)