EWS managed api : Is there a way to identify if an email or attachment is encrypted?

问题

Does EWS managed api expose any property to identify whether an item( email/attachment) is encrypted?

回答1:

 var isEmailOpaqueSignedOrEncrypted = false;

if (email.ItemClass == "IPM.Note.SMIME")
{
    var attList = email.Attachments.ToList();
    if (attList.Count == 1)
    {
        isEmailOpaqueSignedOrEncrypted = true;
    }
};

来源：https://stackoverflow.com/questions/26486144/ews-managed-api-is-there-a-way-to-identify-if-an-email-or-attachment-is-encryp