MimeKit by Jeffrey Stedfast

<PackageReference Include="MimeKit" Version="1.16.0" />

 MessagePart

public class MessagePart : MimeEntity
A MIME part containing a MimeMessage as its content.
public MimeMessage Message { get; set; }

Gets or sets the message content.

Initializes a new instance of the MessagePart class.

public MessagePart(string subtype, object[] args)

Initializes a new instance of the MessagePart class.

public MessagePart(string subtype)

Initializes a new instance of the MessagePart class.

public MessagePart()

Initializes a new instance of the MessagePart class.