NullReferenceException: 未将对象引用设置到对象的实例。
StackTrace:
   在 MS.Internal.TextFormatting.TextMetrics.FullTextLine.FormatLine(FullTextState fullText, Int32 cpFirst, Int32 lineLength, Int32 formatWidth, Int32 finiteFormatWidth, Int32 paragraphWidth, LineFlags lineFlags, FormattedTextSymbols collapsingSymbol)
   在 MS.Internal.TextFormatting.TextMetrics.FullTextLine..ctor(FormatSettings settings, Int32 cpFirst, Int32 lineLength, Int32 paragraphWidth, LineFlags lineFlags)
   在 MS.Internal.TextFormatting.TextFormatterImp.FormatLineInternal(TextSource textSource, Int32 firstCharIndex, Int32 lineLength, Double paragraphWidth, TextParagraphProperties paragraphProperties, TextLineBreak previousLineBreak, TextRunCache textRunCache)
   在 MS.Internal.TextFormatting.TextFormatterImp.FormatLine(TextSource textSource, Int32 firstCharIndex, Double paragraphWidth, TextParagraphProperties paragraphProperties, TextLineBreak previousLineBreak, TextRunCache textRunCache)
   在 System.Windows.Controls.TextBlock.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.AccessText.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.StackPanel.StackMeasureHelper(IStackMeasure measureElement, IStackMeasureScrollData scrollData, Size constraint)
   在 System.Windows.Controls.StackPanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   在 System.Windows.Controls.ContentPresenter.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.StackPanel.StackMeasureHelper(IStackMeasure measureElement, IStackMeasureScrollData scrollData, Size constraint)
   在 System.Windows.Controls.StackPanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Border.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 HandyControl.Controls.SimplePanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Control.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Primitives.ToolBarPanel.MeasureGeneratedItems(Boolean asNeededPass, Size constraint, Boolean horizontal, Double maxExtent, Size& panelDesiredSize, Double& overflowExtent)
   在 System.Windows.Controls.Primitives.ToolBarPanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.DockPanel.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   在 System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   在 System.Windows.Controls.Grid.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Border.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Control.MeasureOverride(Size constraint)
   在 System.Windows.Controls.ToolBar.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.ToolBarTray.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   在 System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   在 System.Windows.Controls.Grid.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint)
   在 System.Windows.Controls.ContentPresenter.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Documents.AdornerDecorator.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV)
   在 System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV, Boolean& hasDesiredSizeUChanged)
   在 System.Windows.Controls.Grid.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Controls.Border.MeasureOverride(Size constraint)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.Window.MeasureOverrideHelper(Size constraint)
   在 System.Windows.Window.MeasureOverride(Size availableSize)
   在 System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   在 System.Windows.UIElement.Measure(Size availableSize)
   在 System.Windows.ContextLayoutManager.UpdateLayout()
   在 System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg)
   在 System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
   在 System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
   在 System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
   在 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   在 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

NullReferenceException: 未将对象引用设置到对象的实例。
StackTrace:
   在 System.Xml.XmlReader.ReadElementString()
   在 MS.Internal.FontFace.CompositeFontParser.ParseFamilyNameElement()
   在 MS.Internal.FontFace.CompositeFontParser.ParseFontFamilyElement()
   在 MS.Internal.FontFace.CompositeFontParser.ParseFontFamilyCollectionElement()
   在 MS.Internal.FontFace.CompositeFontParser..ctor(Stream fileStream)
   在 MS.Internal.FontCache.FamilyCollection.SystemCompositeFonts.GetCompositeFontFamilyAtIndex(Int32 index)
   在 MS.Internal.FontCache.FamilyCollection.LookupFamily(String familyName, FontStyle& fontStyle, FontWeight& fontWeight, FontStretch& fontStretch)
   在 System.Windows.Media.FontFamily.LookupFontFamilyAndFace(CanonicalFontFamilyReference canonicalFamilyReference, FontStyle& style, FontWeight& weight, FontStretch& stretch)
   在 MS.Internal.Shaping.TypefaceMap.MapOnceByFontFamilyList(CharacterBufferRange unicodeString, CultureInfo culture, CultureInfo digitCulture, FontFamily[] familyList, PhysicalFontFamily& firstValidFamily, Int32& firstValidLength, IDeviceFont deviceFont, Double scaleInEm, Int32 recursionDepth, SpanVector scaledTypefaceSpans, Int32 firstCharIndex, Int32& nextValid)
   在 MS.Internal.Shaping.TypefaceMap.MapByFontFamilyList(CharacterBufferRange unicodeString, CultureInfo culture, CultureInfo digitCulture, FontFamily[] familyList, PhysicalFontFamily& firstValidFamily, Int32& firstValidLength, IDeviceFont deviceFont, Double scaleInEm, Int32 recursionDepth, SpanVector scaledTypefaceSpans, Int32 firstCharIndex, Int32& nextValid)
   在 MS.Internal.Shaping.TypefaceMap.MapItem(CharacterBufferRange unicodeString, CultureInfo culture, Span itemSpan, SpanVector`1& cachedScaledTypefaceIndexSpans, Int32 ichItem)
   在 MS.Internal.Shaping.TypefaceMap.GetShapeableText(CharacterBufferReference characterBufferReference, Int32 stringLength, TextRunProperties textRunProperties, CultureInfo digitCulture, Boolean isRightToLeftParagraph, IList`1 shapeableList, IShapeableTextCollector collector, TextFormattingMode textFormattingMode)
   在 MS.Internal.Shaping.GlyphingCache.GetShapeableText(Typeface typeface, CharacterBufferReference characterBufferReference, Int32 stringLength, TextRunProperties textRunProperties, CultureInfo digitCulture, Boolean isRightToLeftParagraph, IList`1 shapeableList, IShapeableTextCollector collector, TextFormattingMode textFormattingMode)
   在 System.Windows.Media.TextFormatting.TextCharacters.MS.Internal.TextFormatting.ITextSymbols.GetTextShapeableSymbols(GlyphingCache glyphingCache, CharacterBufferReference characterBufferReference, Int32 length, Boolean rightToLeft, Boolean isRightToLeftParagraph, CultureInfo digitCulture, TextModifierScope textModifierScope, TextFormattingMode textFormattingMode, Boolean isSideways)
   在 MS.Internal.TextFormatting.TextStore.CreateTextLSRuns(TextRunInfo runInfo, IList`1 textEffects, CultureInfo digitCulture, Int32 offsetToFirstChar, Int32 stringLength, Int32 uniformBidiLevel, TextFormattingMode textFormattingMode, Boolean isSideways, Int32& lastBidiLevel)
   在 MS.Internal.TextFormatting.TextStore.CreateLSRuns(TextRunInfo runInfo, IList`1 textEffects, CultureInfo digitCulture, Int32 offsetToFirstChar, Int32 stringLength, Int32 uniformBidiLevel, TextFormattingMode textFormattingMode, Boolean isSideways, Int32& lastBidiLevel, Int32& textRunLength)
   在 MS.Internal.TextFormatting.TextStore.CreateLSRunsUniformBidiLevel(SpanVector runInfoVector, SpanVector textEffectsVector, Int32 runInfoFirstCp, Int32 ichUniform, Int32 cchUniform, Int32 uniformBidiLevel, TextFormattingMode textFormattingMode, Boolean isSideways, Int32& lastBidiLevel)
   在 MS.Internal.TextFormatting.TextStore.FetchLSRun(Int32 lscpFetch, TextFormattingMode textFormattingMode, Boolean isSideways, Plsrun& plsrun, Int32& lsrunOffset, Int32& lsrunLength)
   在 MS.Internal.TextFormatting.LineServicesCallbacks.FetchRunRedefined(IntPtr pols, Int32 lscpFetch, Int32 fIsStyle, IntPtr pstyle, Char* pwchTextBuffer, Int32 cchTextBuffer, Int32& fIsBufferUsed, Char*& pwchText, Int32& cchText, Int32& fIsHidden, LsChp& lschp, IntPtr& lsplsrun)