private TreeViewItem FindTreeViewItem(ItemsControl container, object item)
        {
            if (null == container || null == item)
            {
                return null;
            }

            if (container.DataContext == item)
            {
                return container as TreeViewItem;
            }

            int count = container.Items.Count;
            for (int i = 0; i < count; i++)
            {
                TreeViewItem subContainer = (TreeViewItem)container.ItemContainerGenerator.ContainerFromIndex(i);

                if (null == subContainer)
                {
                    continue;
                }

                // Search the next level for the object.
                TreeViewItem resultContainer = FindTreeViewItem(subContainer, item);
                if (null != resultContainer)
                {
                    return resultContainer;
                }
            }

            return null;
        }



/////使用上述方法遍历 ， 然后设置IsSelected属性

   private static void SelectedItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            //
            SelectedProtocolControl spc = d as SelectedProtocolControl;

            if (null != spc)
            {
                if (e.NewValue != spc.trvSelectedProtocol.SelectedItem)
                {
                    //TreeViewItem tviNew = spc.trvSelectedProtocol.ItemContainerGenerator.ContainerFromItem(e.NewValue) as TreeViewItem;
                    TreeViewItem tviNew = spc.FindTreeViewItem(spc.trvSelectedProtocol, e.NewValue);
                    if (null != tviNew)
                    {
                        tviNew.IsSelected = true;
                    }
                }

                if (null != e.OldValue)
                {
                    //TreeViewItem tviOld = spc.trvSelectedProtocol.ItemContainerGenerator.ContainerFromItem(e.OldValue) as TreeViewItem;
                    TreeViewItem tviOld = spc.FindTreeViewItem(spc.trvSelectedProtocol, e.OldValue);
                    if (null != tviOld)
                    {
                        tviOld.IsSelected = false;
                    }
                }
            }

            System.Diagnostics.Debug.WriteLine("SelectedItemChanged...");
        }