[Mime] MimeEntity--MimeEntity Mime实体帮助类 (转载)

时间:2021-11-26 03:20:17

点击下载 MimeEntity.rar

这个类是关于Mime实体的类
看下面代码吧

/// <summary>
/// 类说明:Assistant
/// 编 码 人:苏飞
/// 联系方式:361983679
/// 更新网站:[url=http://www.cckan.net/thread-655-1-1.html]http://www.cckan.net/thread-655-1-1.html[/url]
/// </summary>
using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Text;
using System.IO;
using System.Net.Mime;
using System.Net.Mail; namespace DotNet.Utilities
{
/// <summary>
/// This class represents a Mime entity.
/// 这个类表示一个MIME实体
/// </summary>
public class MimeEntity
{
private StringBuilder _encodedMessage;
/// <summary>
/// Gets the encoded message.
/// 获取编码的消息。
/// </summary>
/// <value>
/// 编码的消息
/// The encoded message.
/// </value>
public StringBuilder EncodedMessage
{
get { return _encodedMessage; }
} private List<MimeEntity> _children; /// <summary>
/// Gets the children.
/// </summary>
/// <value>The children.</value>
public List<MimeEntity> Children
{
get
{
return _children;
}
} private ContentType _contentType;
/// <summary>
/// Gets the type of the content.
/// </summary>
/// <value>The type of the content.</value>
public ContentType ContentType
{
get { return _contentType; }
} private string _mediaSubType;
/// <summary>
/// Gets the type of the media sub.
/// </summary>
/// <value>The type of the media sub.</value>
public string MediaSubType
{
get { return _mediaSubType; }
} private string _mediaMainType;
/// <summary>
/// Gets the type of the media main.
/// </summary>
/// <value>The type of the media main.</value>
public string MediaMainType
{
get { return _mediaMainType; }
} private NameValueCollection _headers;
/// <summary>
/// Gets the headers.
/// </summary>
/// <value>The headers.</value>
public NameValueCollection Headers
{
get { return _headers; }
} private string _mimeVersion;
/// <summary>
/// Gets or sets the MIME version.
/// </summary>
/// <value>The MIME version.</value>
public string MimeVersion
{
get
{
return _mimeVersion;
}
set
{
_mimeVersion = value;
}
} private string _contentId;
/// <summary>
/// Gets or sets the content id.
/// </summary>
/// <value>The content id.</value>
public string ContentId
{
get
{
return _contentId;
}
set
{
_contentId = value;
}
} private string _contentDescription;
/// <summary>
/// Gets or sets the content description.
/// </summary>
/// <value>The content description.</value>
public string ContentDescription
{
get
{
return _contentDescription;
}
set
{
_contentDescription = value;
}
} private ContentDisposition _contentDisposition;
/// <summary>
/// Gets or sets the content disposition.
/// </summary>
/// <value>The content disposition.</value>
public ContentDisposition ContentDisposition
{
get
{
return _contentDisposition;
}
set
{
_contentDisposition = value;
}
} private string _transferEncoding;
/// <summary>
/// Gets or sets the transfer encoding.
/// </summary>
/// <value>The transfer encoding.</value>
public string TransferEncoding
{
get
{
return _transferEncoding;
}
set
{
_transferEncoding = value;
}
} private TransferEncoding _contentTransferEncoding;
/// <summary>
/// Gets or sets the content transfer encoding.
/// </summary>
/// <value>The content transfer encoding.</value>
public TransferEncoding ContentTransferEncoding
{
get
{
return _contentTransferEncoding;
}
set
{
_contentTransferEncoding = value;
}
} /// <summary>
/// Gets a value indicating whether this instance has boundary.
/// </summary>
/// <value>
/// <c>true</c> if this instance has boundary; otherwise, <c>false</c>.
/// </value>
internal bool HasBoundary
{
get
{
return (!string.IsNullOrEmpty(_contentType.Boundary))
|| (!string.IsNullOrEmpty(_startBoundary));
}
} private string _startBoundary;
/// <summary>
/// Gets the start boundary.
/// </summary>
/// <value>The start boundary.</value>
public string StartBoundary
{
get
{
if (string.IsNullOrEmpty(_startBoundary) || !string.IsNullOrEmpty(_contentType.Boundary))
{
return string.Concat("--", _contentType.Boundary);
} return _startBoundary;
}
} /// <summary>
/// Gets the end boundary.
/// </summary>
/// <value>The end boundary.</value>
public string EndBoundary
{
get
{
return string.Concat(StartBoundary, "--");
}
} private MimeEntity _parent;
/// <summary>
/// Gets or sets the parent.
/// </summary>
/// <value>The parent.</value>
public MimeEntity Parent
{
get { return _parent; }
set { _parent = value; }
} private MemoryStream _content; /// <summary>
/// Gets or sets the content.
/// </summary>
/// <value>The content.</value>
public MemoryStream Content
{
get { return _content; }
internal set { _content = value; }
} /// <summary>
/// Initializes a new instance of the <see cref="MimeEntity"/> class.
/// </summary>
public MimeEntity()
{
_children = new List<MimeEntity>();
_headers = new NameValueCollection();
_contentType = MimeReader.GetContentType(string.Empty);
_parent = null;
_encodedMessage = new StringBuilder();
} /// <summary>
/// Initializes a new instance of the <see cref="MimeEntity"/> class.
/// </summary>
/// <param name="parent">The parent.</param>
public MimeEntity(MimeEntity parent)
: this()
{
if (parent == null)
{
throw new ArgumentNullException("parent");
} _parent = parent;
_startBoundary = parent.StartBoundary;
} /// <summary>
/// Sets the type of the content.
/// </summary>
/// <param name="contentType">Type of the content.</param>
internal void SetContentType(ContentType contentType)
{
_contentType = contentType;
_contentType.MediaType = MimeReader.GetMediaType(contentType.MediaType);
_mediaMainType = MimeReader.GetMediaMainType(contentType.MediaType);
_mediaSubType = MimeReader.GetMediaSubType(contentType.MediaType);
} /// <summary>
/// Toes the mail message ex.
/// </summary>
/// <returns></returns>
public MailMessageEx ToMailMessageEx()
{
return ToMailMessageEx(this);
} /// <summary>
/// Toes the mail message ex.
/// </summary>
/// <param name="entity">The entity.</param>
/// <returns></returns>
private MailMessageEx ToMailMessageEx(MimeEntity entity)
{
if (entity == null)
{
//throw new ArgumentNullException("entity");
return null;
} //parse standard headers and create base email.
MailMessageEx message = MailMessageEx.CreateMailMessageFromEntity(entity); if (!string.IsNullOrEmpty(entity.ContentType.Boundary))
{
message = MailMessageEx.CreateMailMessageFromEntity(entity);
BuildMultiPartMessage(entity, message);
}//parse multipart message into sub parts.
else if (string.Equals(entity.ContentType.MediaType, MediaTypes.MessageRfc822, StringComparison.InvariantCultureIgnoreCase))
{
//use the first child to create the multipart message.
if (entity.Children.Count < )
{
throw new Pop3Exception("Invalid child count on message/rfc822 entity.");
} //create the mail message from the first child because it will
//contain all of the mail headers. The entity in this state
//only contains simple content type headers indicating, disposition, type and description.
//This means we can't create the mail message from this type as there is no
//internet mail headers attached to this entity.
message = MailMessageEx.CreateMailMessageFromEntity(entity.Children[]);
BuildMultiPartMessage(entity, message);
} //parse nested message.
else
{
message = MailMessageEx.CreateMailMessageFromEntity(entity);
BuildSinglePartMessage(entity, message);
} //Create single part message. return message;
} /// <summary>
/// Builds the single part message.
/// </summary>
/// <param name="entity">The entity.</param>
/// <param name="message">The message.</param>
private void BuildSinglePartMessage(MimeEntity entity, MailMessageEx message)
{
SetMessageBody(message, entity);
} /// <summary>
/// Gets the body encoding.
/// </summary>
/// <param name="contentType">Type of the content.</param>
public Encoding GetEncoding()
{
if (string.IsNullOrEmpty(this.ContentType.CharSet))
{
return Encoding.ASCII;
}
else
{
try
{
return Encoding.GetEncoding(this.ContentType.CharSet);
}
catch (ArgumentException)
{
return Encoding.ASCII;
}
}
} /// <summary>
/// Builds the multi part message.
/// </summary>
/// <param name="entity">The entity.</param>
/// <param name="message">The message.</param>
private void BuildMultiPartMessage(MimeEntity entity, MailMessageEx message)
{
foreach (MimeEntity child in entity.Children)
{
if (child == null)
{
continue;
}
if (string.Equals(child.ContentType.MediaType, MediaTypes.MultipartAlternative, StringComparison.InvariantCultureIgnoreCase)
|| string.Equals(child.ContentType.MediaType, MediaTypes.MultipartMixed, StringComparison.InvariantCultureIgnoreCase))
{
BuildMultiPartMessage(child, message);
} //if the message is mulitpart/alternative or multipart/mixed then the entity will have children needing parsed.
else if (!IsAttachment(child) &&
(string.Equals(child.ContentType.MediaType, MediaTypes.TextPlain)
|| string.Equals(child.ContentType.MediaType, MediaTypes.TextHtml)))
{
message.AlternateViews.Add(CreateAlternateView(child));
SetMessageBody(message, child); } //add the alternative views.
else if (string.Equals(child.ContentType.MediaType, MediaTypes.MessageRfc822, StringComparison.InvariantCultureIgnoreCase)
&& string.Equals(child.ContentDisposition.DispositionType, DispositionTypeNames.Attachment, StringComparison.InvariantCultureIgnoreCase))
{
message.Children.Add(ToMailMessageEx(child));
} //create a child message and
else if (IsAttachment(child))
{
message.Attachments.Add(CreateAttachment(child)); }
}
} private static bool IsAttachment(MimeEntity child)
{
return (child.ContentDisposition != null)
&& (string.Equals(child.ContentDisposition.DispositionType, DispositionTypeNames.Attachment, StringComparison.InvariantCultureIgnoreCase));
} /// <summary>
/// Sets the message body.
/// </summary>
/// <param name="message">The message.</param>
/// <param name="child">The child.</param>
private void SetMessageBody(MailMessageEx message, MimeEntity child)
{
Encoding encoding = child.GetEncoding();
message.Body = DecodeBytes(child.Content.ToArray(), encoding);
message.BodyEncoding = encoding;
message.IsBodyHtml = string.Equals(MediaTypes.TextHtml,
child.ContentType.MediaType, StringComparison.InvariantCultureIgnoreCase);
} /// <summary>
/// Decodes the bytes.
/// </summary>
/// <param name="buffer">The buffer.</param>
/// <param name="encoding">The encoding.</param>
/// <returns></returns>
private string DecodeBytes(byte[] buffer, Encoding encoding)
{
if (buffer == null)
{
return null;
} if (encoding == null)
{
encoding = Encoding.UTF7;
} //email defaults to 7bit. return encoding.GetString(buffer);
} /// <summary>
/// Creates the alternate view.
/// </summary>
/// <param name="view">The view.</param>
/// <returns></returns>
private AlternateView CreateAlternateView(MimeEntity view)
{
AlternateView alternateView = new AlternateView(view.Content, view.ContentType);
alternateView.TransferEncoding = view.ContentTransferEncoding;
alternateView.ContentId = TrimBrackets(view.ContentId);
return alternateView;
} /// <summary>
/// Trims the brackets.
/// </summary>
/// <param name="value">The value.</param>
/// <returns></returns>
public static string TrimBrackets(string value)
{
if (value == null)
{
return value;
} if (value.StartsWith("<") && value.EndsWith(">"))
{
return value.Trim('<', '>');
} return value;
} /// <summary>
/// Creates the attachment.
/// </summary>
/// <param name="entity">The entity.</param>
/// <returns></returns>
private Attachment CreateAttachment(MimeEntity entity)
{
Attachment attachment = new Attachment(entity.Content, entity.ContentType); if (entity.ContentDisposition != null)
{
attachment.ContentDisposition.Parameters.Clear();
foreach (string key in entity.ContentDisposition.Parameters.Keys)
{
attachment.ContentDisposition.Parameters.Add(key, entity.ContentDisposition.Parameters[key]);
} attachment.ContentDisposition.CreationDate = entity.ContentDisposition.CreationDate;
attachment.ContentDisposition.DispositionType = entity.ContentDisposition.DispositionType;
attachment.ContentDisposition.FileName = entity.ContentDisposition.FileName;
attachment.ContentDisposition.Inline = entity.ContentDisposition.Inline;
attachment.ContentDisposition.ModificationDate = entity.ContentDisposition.ModificationDate;
attachment.ContentDisposition.ReadDate = entity.ContentDisposition.ReadDate;
attachment.ContentDisposition.Size = entity.ContentDisposition.Size;
} if (!string.IsNullOrEmpty(entity.ContentId))
{
attachment.ContentId = TrimBrackets(entity.ContentId);
} attachment.TransferEncoding = entity.ContentTransferEncoding; return attachment;
}
}
}