Thư viện .NET mã nguồn mở cho IMAP, POP3 & SMTP

cài đặt Mailkit qua NuGet

Install-Package MailKit  

Cài đặt Bộ thư qua GitHub 

git clone --recursive https://github.com/jstedfast/MailKit.git 

Tạo và gửi tin nhắn miễn phí bằng C #

var message = new MimeMessage();
message.From.Add(new MailboxAddress("fred", "This email address is being protected from spam-bots. You need JavaScript enabled to view it."));
message.To.Add(new MailboxAddress("frans", "This email address is being protected from spam-bots. You need JavaScript enabled to view it."));
message.Subject = "FileFormat ";
message.Body = new TextPart("plain")
{
  Text = "File Format Developer Guide"
};
using (var client = new SmtpClient())
{
  // For demo-purposes,
  client.ServerCertificateValidationCallback = (s, c, h, e) => true;
  client.Connect("smtp.test.com", 587, false);
  // Note: only needed if the SMTP server requires authentication
  client.Authenticate("frans", "password");
  client.Send(message);
  client.Disconnect(true);
}                  

Tạo tin nhắn có tệp đính kèm qua C #

var message = new MimeMessage ();
message.From.Add (new MailboxAddress ("Joey", "joey@friends.com"));
message.To.Add (new MailboxAddress ("Alice", "alice@wonderland.com"));
message.Subject = "How you doin?";
// create our message text, just like before (except don't set it as the message.Body)
var body = new TextPart ("plain") {
  Text = @"Hey Alice,
What are you up to this weekend? Monica is throwing one of her parties on
Saturday and I was hoping you could make it.
Will you be my +1?
-- Joey
"
};
// create an image attachment for the file located at path
var attachment = new MimePart ("image", "gif") {
  Content = new MimeContent (File.OpenRead (path), ContentEncoding.Default),
  ContentDisposition = new ContentDisposition (ContentDisposition.Attachment),
  ContentTransferEncoding = ContentEncoding.Base64,
  FileName = Path.GetFileName (path)
};
// now create the multipart/mixed container to hold the message text and the
// image attachment
var multipart = new Multipart ("mixed");
multipart.Add (body);
multipart.Add (attachment);
// now set the multipart/mixed as the message body
message.Body = multipart;
 

Mã hóa tin nhắn với PGP / MIME qua C #

public void Encrypt (MimeMessage message)
{
  // encrypt our message body using our custom GnuPG cryptography context
  using (var ctx = new MyGnuPGContext ()) {
    // Note: this assumes that each of the recipients has a PGP key associated
    // with their email address in the user's public keyring.
    // 
    // If this is not the case, you can use SecureMailboxAddresses instead of
    // normal MailboxAddresses which would allow you to specify the fingerprint
    // of their PGP keys. You could also choose to use one of the Encrypt()
    // overloads that take a list of PgpPublicKeys.
    message.Body = MultipartEncrypted.Encrypt (ctx, message.To.Mailboxes, message.Body);
  }
}

Giải mã thông báo PGP / MIME

public MimeEntity Decrypt (MimeMessage message)
{
  if (message.Body is MultipartEncrypted) {
    // the top-level MIME part of the message is encrypted using PGP/MIME
    var encrypted = (MultipartEncrypted) entity;
    return encrypted.Decrypt ();
  } else {
    // the top-level MIME part is not encrypted
    return message.Body;
  }
}