使用Exchange管理的API（EWS）监视邮箱附件

PullSubscription subscription = 
SomeExchangeService.SubscribeToPullNotifications(
new FolderId[]{ WellKnownFolderName.Inbox },1440,\"\",EventType.Created);
Subscriptions.Add(subscription);

static void Exchanger_Elapsed(object sender, ElapsedEventArgs e)
    {    
        foreach (var pullSubscription in Subscriptions)
        {
            foreach (var itemEvent in pullSubscription.GetEvents().ItemEvents)
            {
                Item item = Item.Bind(SomeExchangeService, itemEvent.ItemId);
                if (item.Subject == someString)
                {
                  //  item.Attachments do something
                  //  As in read it as a stream and write it 
                  //  to a file according to mime type and file extension
                }
            }
        }
   }

public static List<PullSubscriptionpublic static List<PullSubscription> Subscriptions = new List<PullSubscription>();> Subscriptions = new List<PullSubscription>();