WPF ItemsControl 控件支持鼠标滚轮滑动

此文章意在解决在WPF中ItemsControl类型的集合控件支持鼠标滚轮操作，并可控制滚动的速度。

第一步：给ItemsControl添加滚轮事件。

this.listBox.AddHandler(ListBox.MouseWheelEvent, new MouseWheelEventHandler(list_MouseWheel), true);

第二步：实现list_MouseWheel处理函数。

private void list_MouseWheel(object sender, MouseWheelEventArgs e)
{
            ItemsControl items = (ItemsControl)sender;
            ScrollViewer scroll = FindVisualChild<ScrollViewer>(items);
            scroll.PanningMode = PanningMode.HorizontalOnly;
            if (scroll != null)
            {
                int d = e.Delta;
                if (d > 0)
                {
                    this._HistoryListBox.ScrollSkip(-2);//此方法为集合控件的扩展方法。参数为控制滑动的速度。
                   // scroll.LineRight();
                }
                if (d < 0)
                {
                    //scroll.LineLeft();
                    this._HistoryListBox.ScrollSkip(2);
                }
                scroll.ScrollToTop();
            }
}

第三步：定义集合控件的扩展属性和方法。

  public static class ListBoxExtention
     {
          public static double GetHorizontalOffset(DependencyObject obj)
         {
             return (double)obj.GetValue(HorizontalOffsetProperty);
         }

         public static void SetHorizontalOffset(DependencyObject obj, double value)
         {
             obj.SetValue(HorizontalOffsetProperty, value);
         }

         /// <summary>
         /// 动画属性，控制水平方向移动
         /// </summary>
         public static readonly DependencyProperty HorizontalOffsetProperty = DependencyProperty.RegisterAttached("HorizontalOffset", typeof(double), typeof(ListBoxExtention), new UIPropertyMetadata(0.0, OnHorizontalOffsetPropertyChanged));

         static void OnHorizontalOffsetPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
         {
             ((ScrollViewer)sender).ScrollToHorizontalOffset((double)args.NewValue);
         }

         public static double GetVerticalOffset(DependencyObject obj)
         {
             return (double)obj.GetValue(VerticalOffsetProperty);
         }

         public static void SetVerticalOffset(DependencyObject obj, double value)
         {
             obj.SetValue(VerticalOffsetProperty, value);
         }

         // 用一个依赖属性作为verticaloffset存储器.  这使动画, 样式,绑定, 等等及其他
         public static readonly DependencyProperty VerticalOffsetProperty =DependencyProperty.RegisterAttached("VerticalOffset", typeof(double), typeof(ListBoxExtention), new UIPropertyMetadata(0.0, OnVerticalOffsetPropertyChanged));

         static void OnVerticalOffsetPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
         {
             ((ScrollViewer)sender).ScrollToVerticalOffset((double)args.NewValue);

         public static void ScrollToSelectedItem(this ListBox listbox, object selectedItem)
         {
             ScrollViewer scrollHost = VisualTreeHelper.GetChild(listbox, ) as ScrollViewer;
             for (DependencyObject obj2 = listbox; obj2 != null; obj2 = VisualTreeHelper.GetChild(obj2, ))
             {
                 ScrollViewer viewer = obj2 as ScrollViewer;
                 if (viewer != null)
                 {
                     scrollHost = viewer;
                     break;
                 }
             }
             if (scrollHost != null && scrollHost.IsLoaded)
             {
                 double fromValue = scrollHost.HorizontalOffset;
                 double toValue = 0.0;
                 if (selectedItem != null)
                 {
                     FrameworkElement visual = listbox.ItemContainerGenerator.ContainerFromItem(selectedItem) as FrameworkElement;
                     if (visual != null)
                     {
                         Vector vector = VisualTreeHelper.GetOffset(visual);
                         toValue = (visual.ActualWidth - scrollHost.ViewportWidth) /  + vector.X;
                     }
                 }
                 DoubleAnimation animation = new DoubleAnimation(fromValue, toValue, new TimeSpan(, , , , ), FillBehavior.HoldEnd);
                 scrollHost.BeginAnimation(ListBoxExtention.HorizontalOffsetProperty, animation);
             }
         }

         public static void ScrollSkip(this ListBox listbox, int count)
         {
             ScrollViewer scrollHost = VisualTreeHelper.GetChild(listbox, ) as ScrollViewer;
             for (DependencyObject obj2 = listbox; obj2 != null; obj2 = VisualTreeHelper.GetChild(obj2, ))
             {
                 ScrollViewer viewer = obj2 as ScrollViewer;
                 if (viewer != null)
                 {
                     scrollHost = viewer;
                     break;
                 }
             }
             if (scrollHost != null && scrollHost.IsLoaded)
             {
                 double fromHorizontalOffset = scrollHost.HorizontalOffset;
                 double toHorizontalOffset = 0.0;
                 double fromVerticalOffset = scrollHost.VerticalOffset;
                 double toVerticalOffset = 0.0;
                 toHorizontalOffset = (scrollHost.ExtentWidth / listbox.Items.Count) * count + fromHorizontalOffset;
                 toVerticalOffset = (scrollHost.ExtentHeight / listbox.Items.Count) * count + fromVerticalOffset;

                 if (ScrollViewer.GetHorizontalScrollBarVisibility(listbox) != ScrollBarVisibility.Disabled)
                 {
                     DoubleAnimation animation = new DoubleAnimation(fromHorizontalOffset, toHorizontalOffset, new TimeSpan(, , , , ), FillBehavior.HoldEnd);
                     scrollHost.BeginAnimation(ListBoxExtention.HorizontalOffsetProperty, animation);
                 }
                 if (ScrollViewer.GetVerticalScrollBarVisibility(listbox) != ScrollBarVisibility.Disabled)
                 {
                     DoubleAnimation animation = new DoubleAnimation(fromVerticalOffset, toVerticalOffset, new TimeSpan(, , , , ), FillBehavior.HoldEnd);
                     scrollHost.BeginAnimation(ListBoxExtention.VerticalOffsetProperty, animation);
                 }
             }
         }

         public static void ScrollSkip_Double(this ListBox listbox, Double count)
         {
             ScrollViewer scrollHost = VisualTreeHelper.GetChild(listbox, ) as ScrollViewer;
             for (DependencyObject obj2 = listbox; obj2 != null; obj2 = VisualTreeHelper.GetChild(obj2, ))
             {
                 ScrollViewer viewer = obj2 as ScrollViewer;
                 if (viewer != null)
                 {
                     scrollHost = viewer;
                     break;
                 }
             }
             if (scrollHost != null && scrollHost.IsLoaded)
             {
                 double fromHorizontalOffset = scrollHost.HorizontalOffset;
                 double toHorizontalOffset = 0.0;
                 double fromVerticalOffset = scrollHost.VerticalOffset;
                 double toVerticalOffset = 0.0;
                 toHorizontalOffset = (scrollHost.ExtentWidth / listbox.Items.Count) * count + fromHorizontalOffset;
                 toVerticalOffset = (scrollHost.ExtentHeight / listbox.Items.Count) * count + fromVerticalOffset;

                 if (ScrollViewer.GetHorizontalScrollBarVisibility(listbox) != ScrollBarVisibility.Disabled)
                 {
                     DoubleAnimation animation = new DoubleAnimation(fromHorizontalOffset, toHorizontalOffset, new TimeSpan(, , , , ), FillBehavior.HoldEnd);
                     scrollHost.BeginAnimation(ListBoxExtention.HorizontalOffsetProperty, animation);
                 }
                 if (ScrollViewer.GetVerticalScrollBarVisibility(listbox) != ScrollBarVisibility.Disabled)
                 {
                     DoubleAnimation animation = new DoubleAnimation(fromVerticalOffset, toVerticalOffset, new TimeSpan(, , , , ), FillBehavior.HoldEnd);
                     scrollHost.BeginAnimation(ListBoxExtention.VerticalOffsetProperty, animation);
                 }
             }
         }
     }