MimeKit.MimeMessage.HeadersChanged C# (CSharp) Method

		void HeadersChanged (object o, HeaderListChangedEventArgs e)
		{
			InternetAddressList list;
			byte[] rawValue;
			int index = 0;
			int number;

			switch (e.Action) {
			case HeaderListChangedAction.Added:
				if (addresses.TryGetValue (e.Header.Field, out list)) {
					AddAddresses (e.Header, list);
					break;
				}

				rawValue = e.Header.RawValue;

				switch (e.Header.Id) {
				case HeaderId.MimeVersion:
					MimeUtils.TryParse (rawValue, 0, rawValue.Length, out version);
					break;
				case HeaderId.References:
					references.Changed -= ReferencesChanged;
					foreach (var msgid in MimeUtils.EnumerateReferences (rawValue, 0, rawValue.Length))
						references.Add (msgid);
					references.Changed += ReferencesChanged;
					break;
				case HeaderId.InReplyTo:
					inreplyto = MimeUtils.EnumerateReferences (rawValue, 0, rawValue.Length).FirstOrDefault ();
					break;
				case HeaderId.ResentMessageId:
					resentMessageId = MimeUtils.ParseMessageId (rawValue, 0, rawValue.Length);
					break;
				case HeaderId.MessageId:
					messageId = MimeUtils.ParseMessageId (rawValue, 0, rawValue.Length);
					break;
				case HeaderId.ResentSender:
					MailboxAddress.TryParse (Headers.Options, rawValue, ref index, rawValue.Length, false, out resentSender);
					break;
				case HeaderId.Sender:
					MailboxAddress.TryParse (Headers.Options, rawValue, ref index, rawValue.Length, false, out sender);
					break;
				case HeaderId.ResentDate:
					DateUtils.TryParse (rawValue, 0, rawValue.Length, out resentDate);
					break;
				case HeaderId.Importance:
					switch (e.Header.Value.ToLowerInvariant ().Trim ()) {
					case "high": importance = MessageImportance.High; break;
					case "low": importance = MessageImportance.Low; break;
					default: importance = MessageImportance.Normal; break;
					}
					break;
				case HeaderId.Priority:
					switch (e.Header.Value.ToLowerInvariant ().Trim ()) {
					case "non-urgent": priority = MessagePriority.NonUrgent; break;
					case "urgent": priority = MessagePriority.Urgent; break;
					default: priority = MessagePriority.Normal; break;
					}
					break;
				case HeaderId.XPriority:
					ParseUtils.SkipWhiteSpace (rawValue, ref index, rawValue.Length);

					if (ParseUtils.TryParseInt32 (rawValue, ref index, rawValue.Length, out number)) {
						xpriority = (XMessagePriority) Math.Min (Math.Max (number, 1), 5);
					} else {
						xpriority = XMessagePriority.Normal;
					}
					break;
				case HeaderId.Date:
					DateUtils.TryParse (rawValue, 0, rawValue.Length, out date);
					break;
				}
				break;
			case HeaderListChangedAction.Changed:
			case HeaderListChangedAction.Removed:
				if (addresses.TryGetValue (e.Header.Field, out list)) {
					ReloadAddressList (e.Header.Id, list);
					break;
				}

				ReloadHeader (e.Header.Id);
				break;
			case HeaderListChangedAction.Cleared:
				foreach (var kvp in addresses) {
					kvp.Value.Changed -= InternetAddressListChanged;
					kvp.Value.Clear ();
					kvp.Value.Changed += InternetAddressListChanged;
				}

				references.Changed -= ReferencesChanged;
				references.Clear ();
				references.Changed += ReferencesChanged;

				resentDate = date = DateTimeOffset.MinValue;
				importance = MessageImportance.Normal;
				xpriority = XMessagePriority.Normal;
				priority = MessagePriority.Normal;
				resentMessageId = null;
				resentSender = null;
				inreplyto = null;
				messageId = null;
				version = null;
				sender = null;
				break;
			default:
				throw new ArgumentOutOfRangeException ();
			}
		}