MimeKit将附件添加到从mht文件加载的邮件中

Question

Hi We are trying to develop a mail sending system using MailKit. We have a set of Email Templates which are created using WORD and saved as MHTML files. The whole thing is working fine, when we use MailKit to create a MimeMessage from the MHT file.

But post creating this message, I am not able to see a way of adding attachments to this.

Currently we are trying the following.

private void SendEmail(string templatePath, List<string> attachments)
    {
        // Load the MHT Template
        var mimeMessage = MimeMessage.Load(templatePath);

        mimeMessage.From.Add(new MailBoxAddress("test@Test.com"));
        mimeMessage.To.Add(new MailBoxAddress("test@Test.com"));

        foreach (var attachment in attachments)
        {
            var fileAttachment = new MimePart()
            {
                ContentObject = new ContentObject(File.OpenRead(Path.Combine(attachment), ContentEncoding.Default),
                ContentDisposition = new ContentDisposition(ContentDisposition.Attachment),
                ContentTransferEncoding = ContentEncoding.Binary,
                FileName = Path.GetFileName(attachment)
            };

            // Attachments is a read only Enumerable here.
            mimeMessage.Attachments.Add
        }

    }

Answer 1

You will need to traverse the MIME tree structure of the message until you find the Multipart that you would like to add the "attachment" to and then use the Multipart.Add() method.

Keep in mind that a message is a nested tree structure and not a well-defined structure which has only 1 message body (or even just 2) and a list of attachments. It's a whole lot more complicated than that, so there's literally no way for MimeMessage.Attachments to "do the right thing".

Answer 2

I add the attachment by the BodyBuilder:

BodyBuilder _body = new BodyBuilder
{
    HtmlBody = message
};
_body.Attachments.Add(_fileName, _stream);
_email.Body = _body.ToMessageBody();

See this post stackoverflow