MailKit系列之轉發電子郵件

原文：http://www.it1352.com/429181.html

問題

我嘗試經過MailKit訪問一個IMAP帳號，我設法下載郵件（做爲的MimeMessage），並在某些時候我須要轉發給其餘賬戶。
展現原始郵件的全部信息（不會忽略，標題，正文內容等）的最佳方式是什麼？

解決方案

說「轉發」時，不一樣的人意味着不一樣的想法，因此我想我會提供答案的不一樣含義的我能想到的。

1.轉發（重發）無任何變化的消息 

var message = FetchMessageFromImapServer ();

using (var client = new SmtpClient ()) {
    client.Connect ("smtp.example.com", 465, true);
    client.Authenticate ("username", "password");

    var sender = new MailboxAddress ("My Name", "username@example.com");
    var recipients = new [] { new MailboxAddress ("John Smith", "john@smith.com") };

    // This version of the Send() method uses the supplied sender and
    // recipients rather than getting them from the message's headers.
    client.Send (message, sender, recipients);

    client.Disconnect (true);
}

 

一般人們並不意味着這種類型的「轉發」，雖然。若是他們想從新發送，一般他們會用重發的一個方法。

2.轉發（重發）消息的標準方法 　　

var message = FetchMessageFromImapServer ();

// clear the Resent-* headers in case this message has already been Resent...
message.ResentSender = null;
message.ResentFrom.Clear ();
message.ResentReplyTo.Clear ();
message.ResentTo.Clear ();
message.ResentCc.Clear ();
message.ResentBcc.Clear ();

// now add our own Resent-* headers...
message.ResentFrom.Add (new MailboxAddress ("MyName", "username@example.com"));
message.ResentReplyTo.Add (new MailboxAddress ("MyName", "username@example.com"));
message.ResentTo.Add (new MailboxAddress ("John Smith", "john@smith.com"));
message.ResentMessageId = MimeUtils.GenerateMessageId ();
message.ResentDate = DateTimeOffset.Now;

using (var client = new SmtpClient ()) {
    client.Connect ("smtp.example.com", 465, true);
    client.Authenticate ("username", "password");

    // The Send() method will use the Resent-From/To/Cc/Bcc headers if
    // they are present.
    client.Send (message);

    client.Disconnect (true);
}

 

3.以一個新的消息轉發

有些郵件客戶端可能會將整個郵件做爲新的消息的方式轉發郵件。

var messageToForward = FetchMessageFromImapServer ();

// construct a new message
var message = new MimeMessage ();
message.From.Add (new MailboxAddress ("MyName", "username@example.com"));
message.ReplyTo.Add (new MailboxAddress ("MyName", "username@example.com"));
message.To.Add (new MailboxAddress ("John Smith", "john@smith.com"));

// now to create our body...
var builder = new BodyBuilder ();
builder.TextBody = "Hey John,\r\n\r\nHere's that message I was telling you about...\r\n";
builder.Attachments.Add (new MessagePart { Message = messageToForward });

message.Body = builder.ToMessageBody ();

using (var client = new SmtpClient ()) {
    client.Connect ("smtp.example.com", 465, true);
    client.Authenticate ("username", "password");

    client.Send (message);

    client.Disconnect (true);
}