TransferEncoding Enum

Definition

Namespace:

System.Net.Mime

Assembly:

System.Net.Mail.dll

Specifies the Content-Transfer-Encoding header information for an email message attachment.

public enum class TransferEncoding

public enum TransferEncoding

type TransferEncoding = 

Public Enum TransferEncoding

Inheritance

Object

ValueType

Enum

TransferEncoding

Fields

Name	Value	Description
Unknown	-1	Indicates that the transfer encoding is unknown.
QuotedPrintable	0	Encodes data that consists of printable characters in the US-ASCII character set. See RFC 2406 Section 6.7.
Base64	1	Encodes stream-based data. See RFC 2406 Section 6.8.
SevenBit	2	Used for data that is not encoded. The data is in 7-bit US-ASCII characters with a total line length of no longer than 1000 characters. See RFC2406 Section 2.7.
EightBit	3	The data is in 8-bit characters that may represent international characters with a total line length of no longer than 1000 8-bit characters. For more information about this 8-bit MIME transport extension, see IETF RFC 6152.

Examples

The following code example displays TransferEncoding used by an attachment.

static void DisplayStreamAttachment( Attachment^ a )
{
   Stream^ s = a->ContentStream;
   StreamReader^ reader = gcnew StreamReader( s );
   Console::WriteLine( L"Content: {0}", reader->ReadToEnd() );
   Console::WriteLine( L"Content Type {0}", a->ContentType );
   Console::WriteLine( L"Transfer Encoding {0}", a->TransferEncoding );
   
   // Note that you cannot close the reader before the email is sent. 
   // Closing the reader before sending the email will close the 
   // ContentStream and cause an SmtpException.
   reader = nullptr;
}

public static void DisplayStreamAttachment(Attachment a)
{
    Stream s = a.ContentStream;
    StreamReader reader = new StreamReader(s);
    Console.WriteLine("Content: {0}", reader.ReadToEnd());
    Console.WriteLine("Content Type {0}", a.ContentType.ToString());
    Console.WriteLine("Transfer Encoding {0}", a.TransferEncoding);
    // Note that you cannot close the reader before the email is sent.
    // Closing the reader before sending the email will close the
    // ContentStream and cause an SmtpException.
    reader = null;
}

Remarks

The values in the TransferEncoding enumeration are used with the AttachmentBase.TransferEncoding property.

The Content-Transfer-Encoding header specifies the encoding of the associated message body so that it meets SMTP requirements. SMTP requires data for transport to be in 7-bit US-ASCII characters with lines no longer than 1000 characters.

Content-Transfer-Encoding values are described in detail in RFC 2045 Section 6, available at https://www.ietf.org.