SmtpCapability Enumeration

A capability supported by an SMTP server.

Definition

Namespace: MailKit.Net.Smtp
Assembly: MailKit (in MailKit.dll) Version: 5.0.0
C#
public enum SmtpCapability

Remarks

Capabilities are read as part of the response to the EHLO command that is issued during the connection phase of the SmtpClient.

Example

C# 
                    public static void PrintCapabilities ()
{
    using (var client = new SmtpClient ()) {
        client.Connect ("smtp.gmail.com", 465, SecureSocketOptions.SslOnConnect);

        if (client.Capabilities.Contains (SmtpCapability.Authentication)) {
            var mechanisms = string.Join (", ", client.AuthenticationMechanisms);
            Console.WriteLine ("The SMTP server supports the following SASL mechanisms: {0}", mechanisms);
            client.Authenticate ("username", "password");
        }

        if (client.Capabilities.Contains (SmtpCapability.Size))
            Console.WriteLine ("The SMTP server has a size restriction on messages: {0}.", client.MaxSize);

        if (client.Capabilities.Contains (SmtpCapability.Dsn))
            Console.WriteLine ("The SMTP server supports delivery-status notifications.");

        if (client.Capabilities.Contains (SmtpCapability.EightBitMime))
            Console.WriteLine ("The SMTP server supports Content-Transfer-Encoding: 8bit");

        if (client.Capabilities.Contains (SmtpCapability.BinaryMime))
            Console.WriteLine ("The SMTP server supports Content-Transfer-Encoding: binary");

        if (client.Capabilities.Contains (SmtpCapability.UTF8))
            Console.WriteLine ("The SMTP server supports UTF-8 in message headers.");

        client.Disconnect (true);
    }
}

Members

Size 0 The server supports the SIZE extension and may have a maximum message size limitation (see MaxSize).
Dsn 1 The server supports the DSN extension, allowing clients to specify which (if any) recipients they would like to receive delivery notifications for.
EnhancedStatusCodes 2 The server supports the ENHANCEDSTATUSCODES extension.
Authentication 3 The server supports the AUTH extension, allowing clients to authenticate via supported SASL mechanisms.
EightBitMime 4 The server supports the 8BITMIME extension, allowing clients to send messages using the "8bit" Content-Transfer-Encoding.
Pipelining 5 The server supports the PIPELINING extension, allowing clients to send multiple commands at once in order to reduce round-trip latency.
BinaryMime 6 The server supports the BINARYMIME extension.
Chunking 7 The server supports the CHUNKING extension, allowing clients to upload messages in chunks.
StartTLS 8 The server supports the STARTTLS extension, allowing clients to switch to an encrypted SSL/TLS connection after connecting.
UTF8 9 The server supports the SMTPUTF8 extension.
RequireTLS 10 The server supports the REQUIRETLS extension.

See Also