WPF中TreeView在鼠標右鍵時無法選中問題

        private void TreeView_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
        {
            var treeViewItem = VisualUpwardSearch<TreeViewItem>(e.OriginalSource as DependencyObject) as TreeViewItem;
            if (treeViewItem != null)
            {
                treeViewItem.Focus();
                e.Handled = true;
            }
        }
        static DependencyObject VisualUpwardSearch<T>(DependencyObject source)
        {
            while (source != null && source.GetType() != typeof(T))
                source = VisualTreeHelper.GetParent(source);
            return source;
        }