我有一个带复选框的Datagrid。选择项目后，将选中该复选框并突出显示该行。当我选择了项目时单击DataGridColumnHeader时，所选项目将再次添加到DataGrid的SelectedItems上。因此，如果我当前有2个SelectedItems，如果我单击DataGridColumnHeader，则SelectedItems计数将为4 - 添加的项目是所选项目的副本。
我不知道为什么每当我点击DataGridColumnHeader时都会更新SelectedItems。我的模型上有一个IsSelected属性。我试着调试知道哪个更新了选择，然后我在下面得到了这个外部代码：
PresentationFramework.dll!MS.Internal.Data.PropertyPathWorker.SetValue(object item, object value) + 0x1c5 bytes
PresentationFramework.dll!System.Windows.Data.BindingExpression.UpdateSource(object value) + 0xce bytes
PresentationFramework.dll!System.Windows.Data.BindingExpressionBase.UpdateValue() + 0xa9 bytes
PresentationFramework.dll!System.Windows.Data.BindingExpressionBase.Dirty() + 0x7a bytes
PresentationFramework.dll!System.Windows.Data.BindingExpressionBase.SetValue(System.Windows.DependencyObject d, System.Windows.DependencyProperty dp, object value) + 0x3e bytes
WindowsBase.dll!System.Windows.DependencyObject.SetValueCommon(System.Windows.DependencyProperty dp, object value, System.Windows.PropertyMetadata metadata, bool coerceWithDeferredReference, bool coerceWithCurrentValue, System.Windows.OperationType operationType, bool isInternal) + 0x3b1 bytes
WindowsBase.dll!System.Windows.DependencyObject.SetCurrentValueInternal(System.Windows.DependencyProperty dp, object value) + 0x99 bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.Selector.AdjustNewContainers() + 0x11d bytes
PresentationFramework.dll!System.Windows.Controls.ItemContainerGenerator.SetStatus(System.Windows.Controls.Primitives.GeneratorStatus value) + 0xb0 bytes
PresentationFramework.dll!System.Windows.Controls.ItemContainerGenerator.BatchGenerator.System.IDisposable.Dispose() + 0x22 bytes
PresentationFramework.dll!System.Windows.Controls.VirtualizingStackPanel.MeasureOverrideImpl(System.Windows.Size constraint, ref double? lastPageSafeOffset, ref System.Collections.Generic.List<double> previouslyMeasuredOffsets, bool remeasure) + 0x1e83 bytes
PresentationFramework.dll!System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(System.Windows.Size constraint) + 0x106 bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.DataGridRowsPresenter.MeasureOverride(System.Windows.Size constraint) + 0x3b bytes
PresentationFramework.dll!System.Windows.FrameworkElement.MeasureCore(System.Windows.Size availableSize) + 0x313 bytes
PresentationCore.dll!System.Windows.UIElement.Measure(System.Windows.Size availableSize) + 0x521 bytes
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayout() + 0x569 bytes
PresentationCore.dll!System.Windows.ContextLayoutManager.UpdateLayoutCallback(object arg) + 0x22 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks() + 0x96 bytes
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandlerCore(object resizedCompositionTarget) + 0xdf bytes
PresentationCore.dll!System.Windows.Media.MediaContext.RenderMessageHandler(object resizedCompositionTarget) + 0x2f bytes
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate callback, object args, int numArgs) + 0x5a bytes
WindowsBase.dll!MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(object source, System.Delegate method, object args, int numArgs, System.Delegate catchHandler) + 0x47 bytes
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.InvokeImpl() + 0x281 bytes
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx) + 0x285 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx) + 0x9 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x57 bytes
WindowsBase.dll!System.Windows.Threading.DispatcherOperation.Invoke() + 0x71 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.ProcessQueue() + 0x2e3 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.WndProcHook(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled) + 0xb3 bytes
WindowsBase.dll!MS.Win32.HwndWrapper.WndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled) + 0x14a bytes
WindowsBase.dll!MS.Win32.HwndSubclass.DispatcherCallbackOperation(object o) + 0x80 bytes
WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate callback, object args, int numArgs) + 0x5a bytes
WindowsBase.dll!MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(object source, System.Delegate method, object args, int numArgs, System.Delegate catchHandler) + 0x47 bytes
WindowsBase.dll!System.Windows.Threading.Dispatcher.LegacyInvokeImpl(System.Windows.Threading.DispatcherPriority priority, System.TimeSpan timeout, System.Delegate method, object args, int numArgs) + 0x2bc bytes
WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam) + 0x140 bytes
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame frame) + 0x112 bytes
PresentationFramework.dll!System.Windows.Application.RunInternal(System.Windows.Window window) + 0x17a bytes
PresentationFramework.dll!System.Windows.Application.Run() + 0x67 bytes
UpgradeStudio.exe!UpgradeStudio.App.Main() + 0x70 bytes C#
[Native to Managed Transition]
[Managed to Native Transition]
Microsoft.VisualStudio.HostingProcess.Utilities.dll!Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly() + 0x57 bytes
mscorlib.dll!System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx) + 0x285 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool preserveSyncCtx) + 0x9 bytes
mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x57 bytes
mscorlib.dll!System.Threading.ThreadHelper.ThreadStart() + 0x51 bytes
[Native to Managed Transition]
单击DataGridColumnHeader时，如何阻止选择行？请帮我。谢谢！