Revert "优化代码"

This reverts commit 92bb458345.

Ink Canvas/App.xaml.cs

@@ -299,7 +299,8 @@ namespace Ink_Canvas
             try
             {
                 // 获取主窗口实例并清理PowerPoint进程守护
-                if (Current.MainWindow is MainWindow mainWindow)
+                var mainWindow = Current.MainWindow as MainWindow;
+                if (mainWindow != null)
                 {
                     // 通过反射调用StopPowerPointProcessMonitoring方法
                     var method = mainWindow.GetType().GetMethod("StopPowerPointProcessMonitoring", 

Ink Canvas/Helpers/AvoidFullScreenHelper.cs

@@ -30,7 +30,8 @@ namespace Ink_Canvas.Helpers
 
             if (!(bool)window.GetValue(IsAvoidFullScreenEnabledProperty))
             {
-                if (PresentationSource.FromVisual(window) is HwndSource hwndSource)
+                var hwndSource = PresentationSource.FromVisual(window) as HwndSource;
+                if (hwndSource != null)
                 {
                     hwndSource.AddHook(KeepInWorkingAreaHook);
                     window.SetValue(IsAvoidFullScreenEnabledProperty, true);
@@ -45,7 +46,8 @@ namespace Ink_Canvas.Helpers
 
             if ((bool)window.GetValue(IsAvoidFullScreenEnabledProperty))
             {
-                if (PresentationSource.FromVisual(window) is HwndSource hwndSource)
+                var hwndSource = PresentationSource.FromVisual(window) as HwndSource;
+                if (hwndSource != null)
                 {
                     hwndSource.RemoveHook(KeepInWorkingAreaHook);
                     window.ClearValue(IsAvoidFullScreenEnabledProperty);
@@ -59,7 +61,8 @@ namespace Ink_Canvas.Helpers
         private static IntPtr KeepInWorkingAreaHook(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
         {
             // 只拦截主画布窗口的全屏（最大化）操作
-            if (!(HwndSource.FromHwnd(hwnd)?.RootVisual is Window window)) return IntPtr.Zero;
+            var window = HwndSource.FromHwnd(hwnd)?.RootVisual as Window;
+            if (window == null) return IntPtr.Zero;
             // 这里假设主画布窗口类名为MainWindow（如有不同请调整）
             if (window.GetType().Name != "MainWindow") return IntPtr.Zero;
 

Ink Canvas/Helpers/InkFadeManager.cs

@@ -107,7 +107,8 @@ namespace Ink_Canvas.Helpers
                         {
                             // 将墨迹添加到 inkCanvas 的父容器中，而不是 inkCanvas.Children
                             // 这样可以避免坐标系统问题
-                            if (_mainWindow.inkCanvas.Parent is Panel parent)
+                            var parent = _mainWindow.inkCanvas.Parent as Panel;
+                            if (parent != null)
                             {
                                 parent.Children.Add(strokeVisual);
                             }
@@ -153,7 +154,8 @@ namespace Ink_Canvas.Helpers
                         try
                         {
                             // 从父容器中移除墨迹
-                            if (_mainWindow.inkCanvas?.Parent is Panel parent && parent.Children.Contains(visual))
+                            var parent = _mainWindow.inkCanvas?.Parent as Panel;
+                            if (parent != null && parent.Children.Contains(visual))
                             {
                                 parent.Children.Remove(visual);
                             }
@@ -511,7 +513,8 @@ namespace Ink_Canvas.Helpers
                 originalVisual.Visibility = Visibility.Hidden;
 
                 var segments = new List<UIElement>();
-                if (!(_mainWindow.inkCanvas?.Parent is Panel parent))
+                var parent = _mainWindow.inkCanvas?.Parent as Panel;
+                if (parent == null)
                 {
                     // 如果父容器不是Panel，直接使用InkCanvas
                     parent = null; // 稍后会检查并使用InkCanvas.Children
@@ -867,7 +870,8 @@ namespace Ink_Canvas.Helpers
             try
             {
                 // 从父容器中移除墨迹
-                if (_mainWindow.inkCanvas?.Parent is Panel parent && parent.Children.Contains(visual))
+                var parent = _mainWindow.inkCanvas?.Parent as Panel;
+                if (parent != null && parent.Children.Contains(visual))
                 {
                     parent.Children.Remove(visual);
                 }

Ink Canvas/Helpers/Plugins/BuiltIn/SuperLauncherPlugin.cs

@@ -313,7 +313,8 @@ namespace Ink_Canvas.Helpers.Plugins.BuiltIn
                 var buttonElement = _launcherButton.Element;
 
                 // 查找浮动栏
-                if (!(mainWindow.FindName("StackPanelFloatingBar") is Panel floatingBar))
+                var floatingBar = mainWindow.FindName("StackPanelFloatingBar") as Panel;
+                if (floatingBar == null)
                 {
                     // 如果直接查找失败，则尝试遍历可视树查找
                     Panel floatingBarPanelFromTree = null;
@@ -404,7 +405,8 @@ namespace Ink_Canvas.Helpers.Plugins.BuiltIn
                 var buttonElement = _launcherButton.Element;
 
                 // 查找浮动栏
-                if (!(mainWindow.FindName("StackPanelFloatingBar") is Panel floatingBar))
+                var floatingBar = mainWindow.FindName("StackPanelFloatingBar") as Panel;
+                if (floatingBar == null)
                 {
                     // 如果直接查找失败，则尝试遍历可视树查找
                     Panel floatingBarPanelFromTree = null;

Ink Canvas/Helpers/ScreenDetectionHelper.cs

@@ -25,7 +25,8 @@ namespace Ink_Canvas.Helpers
                     return Screen.PrimaryScreen;
 
                 // 获取窗口的句柄
-                if (!(PresentationSource.FromVisual(window) is HwndSource hwndSource))
+                var hwndSource = PresentationSource.FromVisual(window) as HwndSource;
+                if (hwndSource == null)
                     return Screen.PrimaryScreen;
 
                 // 获取窗口在屏幕上的位置

Ink Canvas/Helpers/WinTabWindowsChecker.cs

@@ -61,7 +61,8 @@ namespace Ink_Canvas.Helpers
                     {
                         if (windowTitle.Length == windowName.Length)
                         {
-                            if (window.GetCurrentPattern(WindowPattern.Pattern) is WindowPattern windowPattern)
+                            WindowPattern windowPattern = window.GetCurrentPattern(WindowPattern.Pattern) as WindowPattern;
+                            if (windowPattern != null)
                             {
                                 return true;
                             }
@@ -69,7 +70,8 @@ namespace Ink_Canvas.Helpers
                     }
                     else
                     {
-                        if (window.GetCurrentPattern(WindowPattern.Pattern) is WindowPattern windowPattern)
+                        WindowPattern windowPattern = window.GetCurrentPattern(WindowPattern.Pattern) as WindowPattern;
+                        if (windowPattern != null)
                         {
                             return true;
                         }

Ink Canvas/MainWindow.xaml.cs

@@ -26,7 +26,6 @@ using System.Windows.Threading;
 using Application = System.Windows.Application;
 using Brushes = System.Windows.Media.Brushes;
 using Button = System.Windows.Controls.Button;
-using ComboBox = System.Windows.Controls.ComboBox;
 using Cursor = System.Windows.Input.Cursor;
 using Cursors = System.Windows.Input.Cursors;
 using DpiChangedEventArgs = System.Windows.DpiChangedEventArgs;
@@ -329,7 +328,8 @@ namespace Ink_Canvas
 
         private void inkCanvas_EditingModeChanged(object sender, RoutedEventArgs e)
         {
-            if (!(sender is InkCanvas inkCanvas1)) return;
+            var inkCanvas1 = sender as InkCanvas;
+            if (inkCanvas1 == null) return;
 
             // 使用辅助方法设置光标
             SetCursorBasedOnEditingMode(inkCanvas1);
@@ -358,7 +358,8 @@ namespace Ink_Canvas
             if (inkCanvas1.EditingMode == InkCanvasEditingMode.Ink) forcePointEraser = !forcePointEraser;
 
             // 处理橡皮擦覆盖层的启用/禁用
-            if (FindName("EraserOverlayCanvas") is Canvas eraserOverlay)
+            var eraserOverlay = FindName("EraserOverlayCanvas") as Canvas;
+            if (eraserOverlay != null)
             {
                 if (inkCanvas1.EditingMode == InkCanvasEditingMode.EraseByPoint)
                 {
@@ -1300,7 +1301,8 @@ namespace Ink_Canvas
             BorderSettingsMask.Background = new SolidColorBrush(Color.FromArgb(1, 0, 0, 0));
 
             // 获取SettingsPanelScrollViewer中的所有GroupBox
-            if (!(SettingsPanelScrollViewer.Content is StackPanel stackPanel)) return;
+            var stackPanel = SettingsPanelScrollViewer.Content as StackPanel;
+            if (stackPanel == null) return;
 
             // 确保所有GroupBox都是可见的
             foreach (var child in stackPanel.Children)
@@ -1515,15 +1517,20 @@ namespace Ink_Canvas
         // 清除所有导航按钮的Tag属性
         private void ClearAllNavButtonTags()
         {
-            if (!(BorderSettings.Child is Grid grid)) return;
+            var grid = BorderSettings.Child as Grid;
+            if (grid == null) return;
 
-            if (!(grid.Children[0] is Border navSidebar)) return;
+            var navSidebar = grid.Children[0] as Border;
+            if (navSidebar == null) return;
 
-            if (!(navSidebar.Child is Grid navGrid)) return;
+            var navGrid = navSidebar.Child as Grid;
+            if (navGrid == null) return;
 
-            if (!(navGrid.Children[1] is ScrollViewer scrollViewer)) return;
+            var scrollViewer = navGrid.Children[1] as ScrollViewer;
+            if (scrollViewer == null) return;
 
-            if (!(scrollViewer.Content is StackPanel stackPanel)) return;
+            var stackPanel = scrollViewer.Content as StackPanel;
+            if (stackPanel == null) return;
 
             foreach (var child in stackPanel.Children)
             {
@@ -1537,24 +1544,30 @@ namespace Ink_Canvas
         // 设置导航按钮的Tag属性
         private void SetNavButtonTag(string tag)
         {
-            if (!(BorderSettings.Child is Grid grid)) return;
+            var grid = BorderSettings.Child as Grid;
+            if (grid == null) return;
 
-            if (!(grid.Children[0] is Border navSidebar)) return;
+            var navSidebar = grid.Children[0] as Border;
+            if (navSidebar == null) return;
 
-            if (!(navSidebar.Child is Grid navGrid)) return;
+            var navGrid = navSidebar.Child as Grid;
+            if (navGrid == null) return;
 
-            if (!(navGrid.Children[1] is ScrollViewer scrollViewer)) return;
+            var scrollViewer = navGrid.Children[1] as ScrollViewer;
+            if (scrollViewer == null) return;
 
-            if (!(scrollViewer.Content is StackPanel stackPanel)) return;
+            var stackPanel = scrollViewer.Content as StackPanel;
+            if (stackPanel == null) return;
 
             foreach (var child in stackPanel.Children)
             {
                 if (child is Button button)
                 {
                     // 检查按钮的ToolTip属性，根据tag设置对应的按钮
+                    string buttonTag = button.Tag as string;
 
                     // 如果按钮的Tag与要设置的tag匹配，则设置Tag
-                    if (button.Tag is string buttonTag && buttonTag.ToLower() == tag.ToLower())
+                    if (buttonTag != null && buttonTag.ToLower() == tag.ToLower())
                     {
                         button.Tag = tag;
                         return;
@@ -2533,7 +2546,8 @@ namespace Ink_Canvas
             try
             {
                 // 获取滑块的轨道元素
-                if (!(slider.Template.FindName("PART_Track", slider) is Track track))
+                var track = slider.Template.FindName("PART_Track", slider) as Track;
+                if (track == null)
                 {
                     // 如果找不到轨道，使用简单方法
                     UpdateSliderValueFromPosition(slider, position);
@@ -2660,7 +2674,8 @@ namespace Ink_Canvas
         {
             try
             {
-                if (sender is ToggleSwitch toggle)
+                var toggle = sender as ToggleSwitch;
+                if (toggle != null)
                 {
                     Settings.ModeSettings.IsPPTOnlyMode = toggle.IsOn;
                     
@@ -2758,7 +2773,8 @@ namespace Ink_Canvas
             
             try
             {
-                if (sender is ComboBox comboBox)
+                System.Windows.Controls.ComboBox comboBox = sender as System.Windows.Controls.ComboBox;
+                if (comboBox != null)
                 {
                     Settings.Appearance.Theme = comboBox.SelectedIndex;
                     

Ink Canvas/MainWindow_cs/MW_BoardControls.cs

@@ -238,8 +238,9 @@ namespace Ink_Canvas
                     RefreshBlackBoardSidePageListView();
                     AnimationsHelper.ShowWithSlideFromBottomAndFade(BoardBorderLeftPageListView);
                     await Task.Delay(1);
-                    if (BlackBoardLeftSidePageListView.ItemContainerGenerator.ContainerFromIndex(
+                    var leftContainer = BlackBoardLeftSidePageListView.ItemContainerGenerator.ContainerFromIndex(
-                            CurrentWhiteboardIndex - 1) is ListViewItem leftContainer)
+                        CurrentWhiteboardIndex - 1) as ListViewItem;
+                    if (leftContainer != null)
                     {
                         ScrollViewToVerticalTop(leftContainer, BlackBoardLeftSidePageListScrollViewer);
                     }
@@ -257,8 +258,9 @@ namespace Ink_Canvas
                     RefreshBlackBoardSidePageListView();
                     AnimationsHelper.ShowWithSlideFromBottomAndFade(BoardBorderRightPageListView);
                     await Task.Delay(1);
-                    if (BlackBoardRightSidePageListView.ItemContainerGenerator.ContainerFromIndex(
+                    var rightContainer = BlackBoardRightSidePageListView.ItemContainerGenerator.ContainerFromIndex(
-                            CurrentWhiteboardIndex - 1) is ListViewItem rightContainer)
+                        CurrentWhiteboardIndex - 1) as ListViewItem;
+                    if (rightContainer != null)
                     {
                         ScrollViewToVerticalTop(rightContainer, BlackBoardRightSidePageListScrollViewer);
                     }

Ink Canvas/MainWindow_cs/MW_BoardIcons.cs

@@ -504,7 +504,8 @@ namespace Ink_Canvas
             BackgroundPalette.Child = stackPanel;
 
             // 获取主窗口中的根网格，确保面板添加到顶层
-            if (FindName("Main_Grid") is Grid mainGrid)
+            Grid mainGrid = FindName("Main_Grid") as Grid;
+            if (mainGrid != null)
             {
                 // 删除可能已存在的BackgroundPalette
                 foreach (UIElement element in mainGrid.Children)
@@ -525,7 +526,8 @@ namespace Ink_Canvas
                 mainGrid.Children.Add(BackgroundPalette);
 
                 // 设置面板位置
-                if (FindName("BoardChangeBackgroundColorBtn") is FrameworkElement clickElement)
+                var clickElement = FindName("BoardChangeBackgroundColorBtn") as FrameworkElement;
+                if (clickElement != null)
                 {
                     Point position = clickElement.TranslatePoint(new Point(0, 0), mainGrid);
                     BackgroundPalette.Margin = new Thickness(
@@ -549,9 +551,10 @@ namespace Ink_Canvas
                     {
                         if (modePanel.Children.Count > 1)
                         {
+                            var whiteboardButton = modePanel.Children[0] as Border;
                             var blackboardButton = modePanel.Children[1] as Border;
 
-                            if (modePanel.Children[0] is Border whiteboardButton && whiteboardButton.Child is TextBlock whiteboardText)
+                            if (whiteboardButton != null && whiteboardButton.Child is TextBlock whiteboardText)
                             {
                                 whiteboardButton.Background = Settings.Canvas.UsingWhiteboard ?
                                     new SolidColorBrush(Color.FromRgb(0x25, 0x63, 0xeb)) :

Ink Canvas/MainWindow_cs/MW_Eraser.cs

@@ -85,8 +85,9 @@ namespace Ink_Canvas
 
             // 根据橡皮擦形状选择对应的图像资源
             string resourceKey = isEraserCircleShape ? "EllipseEraserImageSource" : "RectangleEraserImageSource";
-
+            var imageSource = TryFindResource(resourceKey) as DrawingImage;
-            if (TryFindResource(resourceKey) is DrawingImage imageSource)
+            
+            if (imageSource != null)
             {
                 eraserFeedback.Source = imageSource;
             }

Ink Canvas/MainWindow_cs/MW_FloatingWindowInterceptor.cs

@@ -53,7 +53,8 @@ namespace Ink_Canvas
                 foreach (var kvp in Settings.Automation.FloatingWindowInterceptor.InterceptRules)
                 {
                     var toggleName = $"ToggleSwitch{kvp.Key}";
-                    if (FindName(toggleName) is ToggleSwitch toggle)
+                    var toggle = FindName(toggleName) as ToggleSwitch;
+                    if (toggle != null)
                     {
                         toggle.IsOn = kvp.Value;
                     }

Ink Canvas/MainWindow_cs/MW_Settings.cs

@@ -2895,7 +2895,8 @@ namespace Ink_Canvas
         private async void UpdateChannelSelector_Checked(object sender, RoutedEventArgs e)
         {
             if (!isLoaded) return;
-            if (sender is RadioButton radioButton)
+            var radioButton = sender as RadioButton;
+            if (radioButton != null)
             {
                 string channel = radioButton.Tag.ToString();
                 UpdateChannel newChannel = channel == "Beta" ? UpdateChannel.Beta : UpdateChannel.Release;

Ink Canvas/MainWindow_cs/MW_ShapeDrawing.cs

@@ -489,16 +489,20 @@ namespace Ink_Canvas
             {
                 SetCursorBasedOnEditingMode(inkCanvas);
             }
-            
+
+            // 修复：几何绘制模式下完全禁止触摸轨迹收集
             if (drawingShapeMode != 0)
             {
+                // 确保几何绘制模式下不切换到Ink模式，避免触摸轨迹被收集
                 inkCanvas.EditingMode = InkCanvasEditingMode.None;
 
                 if (isWaitUntilNextTouchDown && dec.Count > 1) return;
                 if (dec.Count > 1)
                 {
+                    // 修复：双曲线绘制时，多指触摸不应该删除第一笔的辅助线
                     if ((drawingShapeMode == 24 || drawingShapeMode == 25) && drawMultiStepShapeCurrentStep == 1)
                     {
+                        // 第二笔绘制双曲线时，只删除第二笔的临时笔画，保留第一笔的辅助线
                         try
                         {
                             inkCanvas.Strokes.Remove(lastTempStroke);
@@ -519,10 +523,13 @@ namespace Ink_Canvas
                     }
                     return;
                 }
-                
+
+                // 修复：双曲线绘制时，第二笔应该基于第一笔的起点，而不是触摸实时位置
                 Point touchPoint = e.GetTouchPoint(inkCanvas).Position;
                 if ((drawingShapeMode == 24 || drawingShapeMode == 25) && drawMultiStepShapeCurrentStep == 1)
                 {
+                    // 第二笔绘制双曲线时，使用触摸位置作为终点，但保持第一笔的起点
+                    // 这里不需要特殊处理，因为MouseTouchMove函数内部已经正确处理了双曲线的绘制逻辑
                     MouseTouchMove(touchPoint);
                 }
                 else
@@ -531,13 +538,15 @@ namespace Ink_Canvas
                     MouseTouchMove(touchPoint);
                 }
 
-                return;
+                return; // 处理完几何绘制后直接返回，不执行后面的代码
             }
-            
+
+            // 其它模式下，允许橡皮、套索、批注等正常工作，不覆盖EditingMode
             if (inkCanvas.EditingMode == InkCanvasEditingMode.EraseByPoint ||
                 inkCanvas.EditingMode == InkCanvasEditingMode.Select ||
                 inkCanvas.EditingMode == InkCanvasEditingMode.Ink)
             {
+                // 允许正常橡皮、套索、批注
             }
         }
 

Ink Canvas/MainWindow_cs/MW_TrayIcon.cs

@@ -211,18 +211,22 @@ namespace Ink_Canvas
                     // 获取全局快捷键管理器
                     var hotkeyManagerField = typeof(MainWindow).GetField("_globalHotkeyManager", 
                         System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
-
+                    var hotkeyManager = hotkeyManagerField?.GetValue(mainWin) as GlobalHotkeyManager;
-                    if (hotkeyManagerField?.GetValue(mainWin) is GlobalHotkeyManager hotkeyManager)
+                    
+                    if (hotkeyManager != null)
                     {
                         // 禁用所有快捷键
                         hotkeyManager.DisableHotkeyRegistration();
                         
                         // 更新菜单项文本和状态
-                        if (sender is MenuItem menuItem)
+                        var menuItem = sender as MenuItem;
+                        if (menuItem != null)
                         {
-                            if (menuItem.Header is SimpleStackPanel headerPanel)
+                            var headerPanel = menuItem.Header as SimpleStackPanel;
+                            if (headerPanel != null)
                             {
-                                if (headerPanel.Children[0] is TextBlock textBlock)
+                                var textBlock = headerPanel.Children[0] as TextBlock;
+                                if (textBlock != null)
                                 {
                                     if (textBlock.Text == "禁用所有快捷键")
                                     {

Ink Canvas/Windows/ScreenshotSelectorWindow.xaml.cs

@@ -517,17 +517,18 @@ namespace Ink_Canvas
         private void Window_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
         {
             // 检查是否点击了UI元素，如果是则不处理选择
-            if (e.Source is FrameworkElement hitElement && (
+            var hitElement = e.Source as FrameworkElement;
-                    hitElement is Ellipse ||
+            if (hitElement != null && (
-                    hitElement is System.Windows.Controls.Button ||
+                hitElement is Ellipse ||
-                    hitElement is Border ||
+                hitElement is System.Windows.Controls.Button ||
-                    hitElement is TextBlock ||
+                hitElement is Border ||
-                    hitElement is StackPanel ||
+                hitElement is TextBlock ||
-                    hitElement is Separator ||
+                hitElement is StackPanel ||
-                    hitElement.Name == "SizeInfoBorder" ||
+                hitElement is Separator ||
-                    hitElement.Name == "HintText" ||
+                hitElement.Name == "SizeInfoBorder" ||
-                    hitElement.Name == "AdjustModeHint" ||
+                hitElement.Name == "HintText" ||
-                    hitElement.Name == "SelectionRectangle"))
+                hitElement.Name == "AdjustModeHint" ||
+                hitElement.Name == "SelectionRectangle"))
             {
                 return;
             }

Ink Canvas/Windows/SettingsViews/SettingsWindow.xaml.cs

@@ -440,14 +440,16 @@ namespace Ink_Canvas.Windows
 
         private void ToggleSwitch_Click(object sender, MouseButtonEventArgs e)
         {
-            if (sender is Border border)
+            var border = sender as Border;
+            if (border != null)
             {
                 // 切换开关状态
                 bool isOn = border.Background.ToString() == "#FF3584E4";
                 border.Background = isOn ? new SolidColorBrush(Color.FromRgb(225, 225, 225)) : new SolidColorBrush(Color.FromRgb(53, 132, 228));
 
                 // 切换内部圆点的位置
-                if (border.Child is Border innerBorder)
+                var innerBorder = border.Child as Border;
+                if (innerBorder != null)
                 {
                     innerBorder.HorizontalAlignment = isOn ? HorizontalAlignment.Left : HorizontalAlignment.Right;
                 }
@@ -555,7 +557,8 @@ namespace Ink_Canvas.Windows
 
         private void OptionButton_Click(object sender, MouseButtonEventArgs e)
         {
-            if (sender is Border border)
+            var border = sender as Border;
+            if (border != null)
             {
                 string tag = border.Tag?.ToString();
                 if (!string.IsNullOrEmpty(tag))
@@ -565,7 +568,8 @@ namespace Ink_Canvas.Windows
 
                     // 设置当前按钮为选中状态
                     border.Background = new SolidColorBrush(Color.FromRgb(225, 225, 225));
-                    if (border.Child is TextBlock textBlock)
+                    var textBlock = border.Child as TextBlock;
+                    if (textBlock != null)
                     {
                         textBlock.FontWeight = FontWeights.Bold;
                     }
@@ -579,7 +583,8 @@ namespace Ink_Canvas.Windows
         private void ClearOtherOptionsInGroup(Border currentBorder, string currentTag)
         {
             // 获取当前按钮所在的父容器
-            if (currentBorder.Parent is StackPanel parent)
+            var parent = currentBorder.Parent as StackPanel;
+            if (parent != null)
             {
                 // 获取组名（Tag中下划线前的部分）
                 string groupName = currentTag.Split('_')[0];
@@ -593,7 +598,8 @@ namespace Ink_Canvas.Windows
                         if (!string.IsNullOrEmpty(childTag) && childTag.StartsWith(groupName + "_"))
                         {
                             border.Background = new SolidColorBrush(Colors.Transparent);
-                            if (border.Child is TextBlock textBlock)
+                            var textBlock = border.Child as TextBlock;
+                            if (textBlock != null)
                             {
                                 textBlock.FontWeight = FontWeights.Normal;
                             }
@@ -770,7 +776,8 @@ namespace Ink_Canvas.Windows
 
                 if (child is Border border && border.Background != null)
                 {
-                    if (border.Background is SolidColorBrush brush && brush.Color.ToString() == "#FFDEDEDE")
+                    var brush = border.Background as SolidColorBrush;
+                    if (brush != null && brush.Color.ToString() == "#FFDEDEDE")
                     {
                         return border;
                     }
@@ -793,7 +800,8 @@ namespace Ink_Canvas.Windows
 
                 if (child is Border border && border.Background != null)
                 {
-                    if (border.Background is SolidColorBrush brush && brush.Color.ToString() == "#FF3584E4")
+                    var brush = border.Background as SolidColorBrush;
+                    if (brush != null && brush.Color.ToString() == "#FF3584E4")
                     {
                         return border;
                     }
@@ -951,7 +959,8 @@ namespace Ink_Canvas.Windows
                 var relativePosition = Math.Max(0, Math.Min(1, adjustedX / effectiveWidth));
 
                 // 更新滑块位置
-                if (!(customSlider.ThumbImage.RenderTransform is TranslateTransform thumbTransform))
+                var thumbTransform = customSlider.ThumbImage.RenderTransform as TranslateTransform;
+                if (thumbTransform == null)
                 {
                     thumbTransform = new TranslateTransform();
                     customSlider.ThumbImage.RenderTransform = thumbTransform;