界面工具栏使用包含下拉菜单的按钮（ToolBarSplitButton）的方法

1、定义一个 CommandItem（注意Mode = SplitButtonMode.Split）：

CommandItem ciImport2PIPCase = new CommandItem("Import2ProvinceIPCase", new ToolBarSplitButton { Mode = SplitButtonMode.Split}) 
{ Text = "导入", ToolTip = "导入到省病案", ImageSource = CImageResources.ImportMR };
CommandItem root = CommandItem.CreateRoot();
root.Children.AddRange(new CommandItem(CommandNames.Catalog, new ToggleButton() { IsThreeState = false, IsChecked = true }),
    ciImport2PIPCase,
    CommandNames.UnNamed, CommandNames.MoveDown, CommandNames.MoveUp, CommandNames.UnNamed, CommandNames.Exit);

 2、添加菜单项到下拉按钮中：

MenuItem _mniCancelImport2PIPCase = new MenuItem() { Header = "取消导入", ToolTip = "取消导入到省病案" };
MenuItem _mniReImport2PIPCase = new MenuItem() { Header = "重新导入", ToolTip = "重新导入到省病案" };
private void InitImport2PIPCaseCommandMenuItems()
{
    ToolBarSplitButton menu = (ToolBarSplitButton)Commands["Import2ProvinceIPCase"].GetTargets().First();
    _mniCancelImport2PIPCase.Command = new DelegateCommand(this.ExecDeleteFromProvinceIPCase);
    menu.Items.Add(_mniCancelImport2PIPCase);
    _mniReImport2PIPCase.Command = new DelegateCommand(this.ExecReImport2ProvinceIPCase);
    menu.Items.Add(_mniReImport2PIPCase);
}

void ExecDeleteFromProvinceIPCase()
{...}

void ExecReImport2ProvinceIPCase()
{...}

以上代码备忘（方便复用回查）