enhance: add Orientation prop for ScrollViewerAttach

src/Shared/HandyControl_Shared/Controls/Attach/ScrollViewerAttach.cs

@@ -1,4 +1,6 @@
-using System.Windows;
+using System;
+using System.Windows;
+using System.Windows.Controls;
 using HandyControl.Data;
 
 namespace HandyControl.Controls
@@ -13,5 +15,42 @@ namespace HandyControl.Controls
 
         public static bool GetAutoHide(DependencyObject element)
             => (bool) element.GetValue(AutoHideProperty);
+
+        public static readonly DependencyProperty OrientationProperty = DependencyProperty.RegisterAttached(
+            "Orientation", typeof(Orientation), typeof(ScrollViewerAttach), new FrameworkPropertyMetadata(ValueBoxes.VerticalBox, FrameworkPropertyMetadataOptions.Inherits, OnOrientationChanged));
+
+        private static void OnOrientationChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (d is ScrollViewer)
+            {
+                return;
+            }
+
+            if (d is System.Windows.Controls.ScrollViewer scrollViewer)
+            {
+                if ((Orientation) e.NewValue == Orientation.Horizontal)
+                {
+                    scrollViewer.PreviewMouseWheel += ScrollViewer_PreviewMouseWheel;
+                }
+                else
+                {
+                    scrollViewer.PreviewMouseWheel -= ScrollViewer_PreviewMouseWheel;
+                }
+            }
+        }
+
+        private static void ScrollViewer_PreviewMouseWheel(object sender, System.Windows.Input.MouseWheelEventArgs e)
+        {
+            var scrollViewer = (System.Windows.Controls.ScrollViewer) sender;
+            scrollViewer.ScrollToHorizontalOffset(Math.Min(Math.Max(0, scrollViewer.HorizontalOffset - e.Delta), scrollViewer.ScrollableWidth));
+
+            e.Handled = true;
+        }
+
+        public static void SetOrientation(DependencyObject element, Orientation value)
+            => element.SetValue(OrientationProperty, ValueBoxes.OrientationBox(value));
+
+        public static Orientation GetOrientation(DependencyObject element)
+            => (Orientation) element.GetValue(OrientationProperty);
     }
 }

src/Shared/HandyControl_Shared/Controls/Other/ScrollViewer.cs

@@ -17,21 +17,6 @@ namespace HandyControl.Controls
 
         private bool _isRunning;
 
-        /// <summary>
-        ///     滚动方向
-        /// </summary>
-        public static readonly DependencyProperty OrientationProperty = DependencyProperty.Register(
-            "Orientation", typeof(Orientation), typeof(ScrollViewer), new PropertyMetadata(Orientation.Vertical));
-
-        /// <summary>
-        ///     滚动方向
-        /// </summary>
-        public Orientation Orientation
-        {
-            get => (Orientation) GetValue(OrientationProperty);
-            set => SetValue(OrientationProperty, value);
-        }
-
         /// <summary>
         ///     是否响应鼠标滚轮操作
         /// </summary>
@@ -53,7 +38,7 @@ namespace HandyControl.Controls
 
             if (!IsInertiaEnabled)
             {
-                if (Orientation == Orientation.Vertical)
+                if (ScrollViewerAttach.GetOrientation(this) == Orientation.Vertical)
                 {
                     base.OnMouseWheel(e);
                 }
@@ -68,7 +53,7 @@ namespace HandyControl.Controls
             }
             e.Handled = true;
 
-            if (Orientation == Orientation.Vertical)
+            if (ScrollViewerAttach.GetOrientation(this) == Orientation.Vertical)
             {
                 if (!_isRunning)
                 {