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I'm using Delphi 2006 to create and send an email message with an attachment in a personal-use-only application. I send the message with an instance of TIdSMTP, and then also put a copy into a specific IMAP folder with an instance of TIdIMAP4. This all works very nicely with the version of Indy 10 that was distributed with BDS2006, with one exception: the time is always incorrect in the email header.

I decided to fix that if I could, and after searching for a solution it seemed most reasonable to get the latest Indy 10 snapshot and use that.

That puts the correct time into the email header, but there's a new problem. The boundary string is now different in the header of the message that is added to the IMAP folder than what comes in the body of the email! (Please note that the message that was sent via SMTP is correct.)

This is the relevant header information from the older version of Indy 10:

Content-Type: multipart/mixed; boundary="XNlC6OyS4QSiHY2U=_jsXyps6TR34pFNsh"
MIME-Version: 1.0
Date: Tue, 22 Nov 2011 09:11:58 +0000

A test of the BDS2006-bundled version of Indy

--XNlC6OyS4QSiHY2U=_jsXyps6TR34pFNsh
Content-Type: application/octet-stream;
        name="20111122.xls"

And this is the same header information from Indy 10.5.8 (snapshot 10_4702 which I installed yesterday):

Content-Type: multipart/mixed; boundary="CDbEncbFvL7RZdOJ3DOIRoRBs=_nBsbZms"
MIME-Version: 1.0
Date: Tue, 22 Nov 2011 07:33:46 -0600

investigating more deeply, why does the boundary indicator change?

--h=_WzGWJei29fng7SqdPpDh1nkJxJZhiGc
Content-Type: application/octet-stream;
    name="20111122.xls"

The time stamp is fixed, but now the boundary string is incorrect. The result is that there appears to be nothing at all in the message that gets added to my IMAP folder.

Here is the relevant code that creates the email message and attachment, sends it, and puts a copy into the IMAP folder:

  FTheMsg.Date := Now;  // FTheMsg is a component dropped onto the form
  FTheMsg.Recipients.EMailAddresses := edMailTo.Text;
  FTheMsg.ClearBody;
  FTheMsg.Subject := 'Glucose Readings ' + FormatDateTime('mm/dd/yy', FStartDate) + ' - ' +
              FormatDateTime('mm/dd/yy', FEndDate);
  FTheMsg.Body.Assign(FMemo.Lines);

  // create the attachment
  TIdAttachmentFile.Create(FTheMsg.MessageParts, fileName);

  // send the mail!
  FSmtp.Host := FSMTPHost;  // values set up elsewhere, FSmtp is a component on the form
  FImap.Host := FIMAPHost;  // FImap is also a component on the form

  FSmtp.Connect;
  try
    FSmtp.Send(FTheMsg);
    FImap.Connect;
    try
      if (not FImap.AppendMsg('Sent Items', FTheMsg, FTheMsg.LastGeneratedHeaders, [mfSeen]))     then
        StatusBar1.Panels[4].Text := 'Failed append msg';
    finally
      FImap.Disconnect;
    end;
  finally
    FSmtp.Disconnect;
  end;

As I said, the email that gets sent is fine and displays properly. But the one that is added to my IMAP folder (in FImap.AppendMsg() above) is incorrect. I've attempted to trace through the code to see where it might be going wrong, but frankly, I'm not familiar enough with Indy and the various email protocols/RFCs to be able to determine what's going wrong. About all I can tell is that the older version saves the message to a temporary file before appending it to the folder, while the newer version saves it to a memory stream instead. Obviously, something is different about that, but I'm currently too ignorant to determine what.

Is there a simple way to correct the timestamp problem in the old version? If so, that would be fine for my use, as everything else appears to be correct. If not, what else do I need to do to fix the problem exhibited here with the incorrect boundary string?

(As this is an application strictly for my own use, I can live with the incorrect date if I have to, but not with the "empty-appearing" copy in my 'Sent Items' folder.)

If more information is needed, I'll gladly supply whatever I can.

[Edit: I did incorporate something of a kludge in MY code, using the older version of Indy. I simply set the date/time of the message to UTC/GMT time before sending it, and that, at least, allows the message to contain the correct time at the receiver's end. I don't particularly care for that fix, but it does the trick.]

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1 回答 1

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TIdMessage.Body当存在附件时，不要使用该属性来保存您的文本。而是将文本放入TIdText对象中。更好的是，使用TIdMessageBuilder...类，例如TIdMessageBuilderPlain，为你准备TIdMessage身体。

尝试这个：

FTheMsg.Clear; 
FTheMsg.Date := Now;  // FTheMsg is a component dropped onto the form 
FTheMsg.Recipients.EMailAddresses := edMailTo.Text; 
FTheMsg.Subject := 'Glucose Readings ' + FormatDateTime('mm/dd/yy', FStartDate) + ' - ' + FormatDateTime('mm/dd/yy', FEndDate); 
FTheMsg.ContentType := 'multipart/mixed'; 

TIdText.Create(FTheMsg.MessageParts, FMemo.Lines).ContentType := 'text/plain';
TIdAttachmentFile.Create(FTheMsg.MessageParts, fileName); 

FSmtp.Connect; 
try 
  FSmtp.Send(FTheMsg); 
  FImap.Connect; 
  try 
    if (not FImap.AppendMsg('Sent Items', FTheMsg, nil, [mfSeen])) then 
      StatusBar1.Panels[4].Text := 'Failed append msg'; 
  finally 
    FImap.Disconnect; 
  end; 
finally 
  FSmtp.Disconnect; 
end;

或者：

FTheMsg.Clear; 
FTheMsg.Date := Now;  // FTheMsg is a component dropped onto the form 
FTheMsg.Recipients.EMailAddresses := edMailTo.Text; 
FTheMsg.Subject := 'Glucose Readings ' + FormatDateTime('mm/dd/yy', FStartDate) + ' - ' + FormatDateTime('mm/dd/yy', FEndDate); 

with TIdMessageBuilderPlain.Create do
try
  PlainText.Assign(FMemo.Lines);
  Attachments.Add(fileName); 
  FillMessage(FTheMsg);
finally
  Free;
end;

FSmtp.Connect; 
try 
  FSmtp.Send(FTheMsg); 
  FImap.Connect; 
  try 
    if (not FImap.AppendMsg('Sent Items', FTheMsg, nil, [mfSeen])) then 
      StatusBar1.Panels[4].Text := 'Failed append msg'; 
  finally 
    FImap.Disconnect; 
  end; 
finally 
  FSmtp.Disconnect; 
end;

现在，话虽如此，它很可能仍然无法正常工作。 TIdIMAP4.AppendMsg()内部调用TIdMessage.SaveToStream()，它会重新生成新鲜的电子邮件内容（从而改变正文中使用的边界）。无论您是传入预先存在的TIdMessage.LastGeneratedHeaders还是让TIdIMAP4.AppendMsg()抓取当前的TIdMessage.Headers，它们都将与TIdMessage.SaveToStream()生成的新边界不同步。

为确保 SMTP 和 IMAP4 同步，它们需要接收相同的数据。尝试TIdMessage.SaveToStream()先手动调用，并将TIdMessage.NoEncode属性设置为 False，然后将属性设置为 True，然后TIdMessage.NoDecode调用TIdMessage.LoadFromStream()以将保存的数据按原样重新加载到TIdMessage.HeadersandTIdMessage.Body属性中，然后调用TIdSMTP.Send()and TIdIMAP4.AppendMsg()，并将TIdMessage.NoEncode属性设置为 True，以便按原样发送TIdMessage.Headersand 。TIdMessage.Body

我知道，这与TIdIMAP4.AppendMsg()评论/文档所说的背道而驰。 AppendMsg()目前根本不考虑 MIME，因此它不能确保 header 和 body 中的 MIME 边界相互匹配。我将尝试检查修复。对于 Indy 11，Indy 的整个 MIME 处理系统将重新设计，因此我将确保可以保留边界和/或指定自定义边界，以便AppendMsg()更好地匹配正文边界和标题边界。

IMAP4 通常是一个非常棘手的协议。

于 2011-11-22T18:58:49.803 回答