toosbar里面样式为“tbrdropdown”的代码问题

Private Sub ToolbarFrm_ButtonClick(ByVal Button As Object)
On Error GoTo Err_ToolbarFrm_ButtonClick_Click
    Select Case Button
   
    Case "保存"
    Call aaaa("设计录入", Me.Name, 0)
  
   
    Case "取消"
    Call aaaa("设计录入", Me.Name, 0)
    
    Case "新增"
    Call aaaa("设计录入", Me.Name, 1)
     
    Case "导出EXECL"   这个按钮样式为tbrdropdown  有两个下拉按钮 请问这个下拉按钮的点击代码怎么写？

 
    Case "关闭"
    DoCmd.Close
       
       
    End Select
   

Exit_ToolbarFrm_ButtonClick_Click:
    Exit Sub

Err_ToolbarFrm_ButtonClick_Click:
   ' MsgBox Err.Description, , "错误"
    Resume Exit_ToolbarFrm_ButtonClick_Click
End Sub