使用Exchange Web Services从Exchange下载附件

Question

我正在尝试使用以下代码在C＃和Exchange Web Services中连接并下载收件箱中的电子邮件附件，但是我遇到了'System.ArgumentOutOfRangeException'错误，我不知道原因。 我已经搜索过答案，但找不到一个，或者我找到的答案都适用于非常旧的EWS版本。

我知道代码的其余部分通常可行，因为我可以访问与电子邮件相关的其他信息，只是无法访问附件。

有人能帮我指出我的错误吗？

提前感谢，

詹姆斯

    static void Main(string[] args)
    {
        ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2007_SP1);
        service.Credentials = new NetworkCredential("MYLOGIN", "MYPASSWORD", "MYDOMAIN");

        service.Url = new Uri("https://MYMAILSERVER/EWS/Exchange.asmx");

        ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };

        FindItemsResults<Item> findResults = service.FindItems(WellKnownFolderName.Inbox, new ItemView(1000));

        foreach (Item item in findResults.Items)
        {
            if (item.HasAttachments && item.Attachments[0] is FileAttachment)
            {
                FileAttachment fileAttachment = item.Attachments[0] as FileAttachment;
                fileAttachment.Load("C:\\temp\\" + fileAttachment.Name);
            }

        }
    }
}

问题已解决，但出现了新的问题

我已经通过将“foreach（Item item in findResults.Items）”更改为“foreach（EmailMessage item in findResults.Items）”来解决问题，但现在我需要找出如何枚举附件 - 有任何想法的人吗？

- Jimbo James

---

你在哪里得到了异常？哪个参数超出了范围？这些信息通常是异常的一部分。 - Martin Liversage

这是一个索引超出范围的错误。我已经通过将“foreach（Item item in findResults.Items）”更改为“foreach（EmailMessage item in findResults.Items）”来解决了这个问题。 - Jimbo James

"InnerException" 的部分可能也值得关注，以获取那种信息。 - Daniel Frear

Answer 1

请查看您的个人资料。如果您使用的是“轻量级模式”，则附件不会随消息一起下载。

请添加以下行：

item.Load() // loads the entire message with attachment

- vikas

Answer 2

你新问题的答案是：

    ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2007_SP1);

    //service.Credentials = new NetworkCredential( "{Active Directory ID}", "{Password}", "{Domain Name}" );

    service.AutodiscoverUrl("[e-mail]");

        FindItemsResults<Item> findResults = service.FindItems(
           WellKnownFolderName.Inbox,
           new ItemView(10));

        foreach (Item item in findResults.Items)
        {
            Console.WriteLine(item.Subject);
            item.Load();
            if(item.HasAttachments)
            {
                foreach (var i in item.Attachments)
                {
                    FileAttachment fileAttachment = i as FileAttachment;
                    fileAttachment.Load();
                    Console.WriteLine("FileName: " + fileAttachment.Name);

                }
            }

        }

- Nigel Findlater

Answer 3

除非我漏掉了什么明显的东西，你所需要做的就是枚举 item.Attachments。

点击这里并向下滚动到看到Example标题的位置。

- Mike

Answer 4

这是一个名为GetAttachmentsFromEmail的方法，您可以使用它来下载附件。

public static void GetAttachmentsFromEmail(ExchangeService service, ItemId itemId)
    {
        // Bind to an existing message item and retrieve the attachments collection.
        // This method results in an GetItem call to EWS.
        EmailMessage message = EmailMessage.Bind(service, itemId, new PropertySet(ItemSchema.Attachments));

        // Iterate through the attachments collection and load each attachment.
        foreach (Attachment attachment in message.Attachments)
        {
            if (attachment is FileAttachment)
            {
                FileAttachment fileAttachment = attachment as FileAttachment;

                // Load the attachment into a file.
                // This call results in a GetAttachment call to EWS.
                fileAttachment.Load("C:\\temp\\" + fileAttachment.Name);

                Console.WriteLine("File attachment name: " + fileAttachment.Name);
            }
            else // Attachment is an item attachment.
            {
                ItemAttachment itemAttachment = attachment as ItemAttachment;

                // Load attachment into memory and write out the subject.
                // This does not save the file like it does with a file attachment.
                // This call results in a GetAttachment call to EWS.
                itemAttachment.Load();

                Console.WriteLine("Item attachment name: " + itemAttachment.Name);
            }
        }
    }

- RafalP

Answer 5

下载指定数量电子邮件的所有附件的解决方案：

  ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2013);
  service.Credentials = new NetworkCredential("login", "password");

  service.Url = new Uri("https://mail.Yourservername.com/EWS/Exchange.asmx");

  ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };

  FindItemsResults<Item> findResults = service.FindItems(WellKnownFolderName.Inbox, new ItemView(10));

  if (findResults != null && findResults.Items != null && findResults.Items.Count > 0)
      foreach (EmailMessage item in findResults)
       {
         EmailMessage message = EmailMessage.Bind(service, item.Id, new PropertySet(BasePropertySet.IdOnly, ItemSchema.Attachments, ItemSchema.HasAttachments));
           foreach (Attachment attachment in message.Attachment
             {
               if (attachment is FileAttachment)
                  {
                    FileAttachment fileAttachment = attachment as FileAttachment;      
                    fileAttachment.Load(@"Folder\file.name");
                   }
             }
        }

不要忘记向ExchangeService构造函数传递正确的Exchange Server版本。

- Andrei Karcheuski