Outlook VSTO加载项，与电子邮件和附件交互

由于VSTO是在现代Outlook上创建加载项的首选方式，我想知道是否可以从这样的加载项访问电子邮件及其附件？据我了解，作为沙盒Web应用程序的VSTO非常有限。

Since VSTO Is the preferred way to create add-ins on modern Outlook, I was wondering if it's possible to access emails and their attachments from such an add-in? To my understanding, VSTO, being a sandboxed web application, is very limited.

基本上我需要允许用户通过拖动将Outlook消息和附件上传（存档）到远程服务器 - 将它们放到我的加载项窗格中。

Basically I need to allow the user to upload (archive) outlook messages and attachments to a remote server, by dragging-and-dropping them onto my add-in pane.

只使用纯VSTO（web）apis进行此类交互，而不使用原生.COM附加API？是否有可能在Outlook for Mac上做这样的事情，只支持VSTO，没有VBA / .COM？

Is such interaction possible by only using pure VSTO (web) apis, without using native .COM add-in APIs? Is it possible to do anything like that on Outlook for Mac, that supports only VSTO, and no VBA/.COM?

感谢您的帮助！