Joshi.Utils.Imap.Imap.GetMessageSize C# (CSharp) Method

        public long GetMessageSize(string sUid)
        {
            if (String.IsNullOrEmpty(sUid))
            {
                throw new ImapException(ImapException.ImapErrorEnum.IMAP_ERR_INVALIDPARAM, "Invalid uid");
            }
            ImapResponseEnum eImapResponse = ImapResponseEnum.IMAP_SUCCESS_RESPONSE;

            if (!m_bIsLoggedIn)
            {
                try
                {
                    Restore(false);
                }
                catch (ImapException e)
                {
                    if (e.Type != ImapException.ImapErrorEnum.IMAP_ERR_INSUFFICIENT_DATA)
                        throw e;

                    throw new ImapException(ImapException.ImapErrorEnum.IMAP_ERR_NOTCONNECTED);
                }
            }
            if (!m_bIsFolderSelected && !m_bIsFolderExamined)
            {
                throw new ImapException(ImapException.ImapErrorEnum.IMAP_ERR_NOTSELECTED);
            }

            ArrayList asResultArray = new ArrayList();
            string sCommand = IMAP_UIDFETCH_COMMAND;
            sCommand += " " + sUid + " " + IMAP_RFC822_SIZE_COMMAND + IMAP_COMMAND_EOL;
            try
            {
                eImapResponse = SendAndReceive(sCommand, ref asResultArray);
                if (eImapResponse != ImapResponseEnum.IMAP_SUCCESS_RESPONSE)
                {
                    throw new ImapException(ImapException.ImapErrorEnum.IMAP_ERR_SEARCH, asResultArray[0].ToString());
                }
                string sLastLine = IMAP_SERVER_RESPONSE_OK;
                string sBodyStruct = "";
                bool bResult = false;
                int nStart = -1;
                foreach (string sLine in asResultArray)
                {
                    nStart = sLine.IndexOf(IMAP_FETCH_COMMAND);
                    if (sLine.StartsWith(IMAP_UNTAGGED_RESPONSE_PREFIX) &&
                        (nStart != -1))
                    {
                        sBodyStruct = sLine;
                    }
                    else if (sLine.StartsWith(sLastLine))
                    {
                        bResult = true;
                        break;
                    }
                }
                if (!bResult)
                {
                    throw new ImapException(ImapException.ImapErrorEnum.IMAP_ERR_FETCHSIZE);
                }
                nStart = sBodyStruct.IndexOf(IMAP_RFC822_SIZE_COMMAND);
                int nEnd = sBodyStruct.IndexOf(")");
                string size = sBodyStruct.Substring(nStart + IMAP_RFC822_SIZE_COMMAND.Length,
                                                    nEnd - (nStart + IMAP_RFC822_SIZE_COMMAND.Length));

                return Convert.ToUInt32(size.Trim());

            }
            catch (Exception e)
            {
                throw e;
            }
        }