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Daniel Collingwood edited this page Oct 23, 2023 · 14 revisions
classDiagram
    SmtpSender --> EmailWriter
    ImapReceiver --> MailFolderClient
    ImapReceiver --> MailFolderReader
    ImapReceiver --> MailFolderMonitor
    class SmtpSender{
      +ISmtpClient SmtpClient
      +IEmailWriter WriteEmail
      +Task SendAsync()
      +Task TrySendAsync()
    }
    class EmailWriter{
      +MimeMessage MimeMessage
      +IEmailWriter From()
      +IEmailWriter To()
      +IEmailWriter BodyHtml()
      +IEmailWriter Attach()
    }
    class ImapReceiver{
      +IImapClient ImapClient
      +IMailFolderReader ReadMail
      +IMailFolderMonitor MonitorFolder
      +IMailFolderClient MailFolderClient
      +ValueTask<IMailFolder> ConnectMailFolderAsync()
    }
    class MailFolderClient{
      +IMailFolder SentFolder
      +IMailFolder DraftsFolder
      +IMailFolder JunkFolder
      +IMailFolder TrashFolder
      +Task<UniqueId> MoveToAsync()
      +Task<UniqueId> AppendSentMessageAsync()
    }
    class MailFolderReader{
      +IMailReader Top()
      +IMailReader Skip()
      +IMailReader Take()
      +IMailReader Query()
      +IMailReader Range()
      +IMailReader Items()
      +Task GetMessageSummariesAsync()
      +Task GetMimeMessagesAsync()
      +Task GetMimeMessagesEnvelopeBodyAsync()
    }
    class MailFolderMonitor{
      +IMailFolderMonitor OnMessageArrival()
      +IMailFolderMonitor OnMessageDeparture()
      +Task IdleAsync()
    }
    class MimeMessageReader{
      +MimeMessage MimeMessage
      +string BodyText
      +IEnumerable<string> AttachmentNames
      +Task DownloadAllAttachmentsAsync()
      +Task SaveAsync()
      +string ToString()
    }
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MailKitSimplified Code Size

Sending and receiving emails sounds simple, after all, electronic mail existed decades before the Internet. If you're looking for an all-in-one .NET solution for email, you'll quickly discover MailKit is recommended by even the likes of Microsoft due to how it implements the RFC standard. Unfortunately the downside of doing it all is that MailKit can be difficult to set up and use, especially the first time you go to try something like working with attachments or writing a reply. The aim of this package is to make sending and receiving emails as simple as possible!

SMTP with MailKitSimplified.Sender NuGet Downloads

Sending an email with MailKitSimplified.Sender is as easy as:

using var smtpSender = SmtpSender.Create("localhost");
await smtpSender.WriteEmail.To("test@localhost").SendAsync();

IMAP with MailKitSimplified.Receiver NuGet Downloads

Receiving emails with MailKitSimplified.Receiver is as easy as:

using var imapReceiver = ImapReceiver.Create("localhost");
var mimeMessages = await imapReceiver.ReadMail.Top(1).GetMimeMessagesAsync();

You can even monitor an email folder for new messages asynchronously, never before has it been this easy!

await imapReceiver.MonitorFolder.OnMessageArrival(m => Console.WriteLine(m.UniqueId)).IdleAsync();

Once you've got either a mime message or a message summary, replying is now equally as intuitive.

var mimeReply = mimeMessage.GetReplyMessage("<p>Reply here.</p>").From("[email protected]");

You're welcome. 🥲

Example Usage Development Release

The examples above will actually work with no other setup if you use something like smtp4dev (e.g. docker run -d -p 3000:80 -p 25:25 -p 143:143 rnwood/smtp4dev), but below are some more realistic examples. The cancellation token is recommended but not required.

Sending Mail

using var smtpSender = SmtpSender.Create("smtp.example.com:587")
    .SetCredential("[email protected]", "App1icati0nP455w0rd")
    .SetProtocolLog("Logs/SmtpClient.txt");
await smtpSender.WriteEmail
    .From("[email protected]")
    .To("[email protected]")
    .Bcc("[email protected]")
    .Subject("Hello World")
    .BodyHtml("<p>Hi</p>")
    .Attach("appsettings.json")
    .TryAttach(@"Logs\ImapClient.txt")
    .SendAsync(cancellationToken);

See the MailKitSimplified.Sender wiki for more information.

Receiving Mail

using var imapReceiver = ImapReceiver.Create("imap.example.com:993")
    .SetCredential("[email protected]", "App1icati0nP455w0rd")
    .SetProtocolLog("Logs/ImapClient.txt")
    .SetFolder("INBOX");
var mimeMessages = await imapReceiver.ReadMail.Top(10)
    .GetMimeMessagesAsync(cancellationToken);

To only download the message parts you want to use:

var reader = imapReceiver.ReadMail
    .Skip(0).Take(250, continuous: true)
    .Items(MessageSummaryItems.Envelope);
var messageSummaries = await reader.GetMessageSummariesAsync(cancellationToken);

Note: MailKit returns results in ascending order by default, use messageSummaries.Reverse() to get descending results or imapReceiver.ReadMail.Top(#) to get the newest results.

To query unread emails from the IMAP server:

var messageSummaries = await imapReceiver.ReadFrom("INBOX/Subfolder")
    .Query(SearchQuery.NotSeen)
    .ItemsForMimeMessages()
    .GetMessageSummariesAsync(cancellationToken);

To asynchronously monitor the mail folder for incoming messages:

await imapReceiver.MonitorFolder
    .SetMessageSummaryItems()
    .SetIgnoreExistingMailOnConnect()
    .OnMessageArrival(OnArrivalAsync)
    .IdleAsync(cancellationToken);

To asynchronously forward or reply to message summaries as they arrive:

async Task OnArrivalAsync(IMessageSummary messageSummary)
{
    var mimeForward = await messageSummary.GetForwardMessageAsync(
        "<p>FYI.</p>", includeMessageId: true);
    mimeForward.From.Add("[email protected]");
    mimeForward.To.Add("[email protected]");
    //logger.LogInformation($"Reply: \r\n{mimeForward.HtmlBody}");
    //await smtpSender.SendAsync(mimeForward, cancellationToken);
}

See the MailKitSimplified.Receiver wiki for more information.

See Also License

Examples of things like dependency injection, a hosted service, or an ASP.NET API can also be found in the GitHub samples.