C# Mail POP

最近在郵件發送失敗率的統計，要從GMail中抓取郵件發送失敗信息；在網上找了一段C#代碼就是抓不到數據
using System;
using System.Net.Sockets;
using System.Net;
using System.Security.Cryptography;
using System.IO;
using System.Data;

namespace GetMail
{

  /// <summary> 
  /// 获取邮件(的)类 
  /// zgke@sina.com 
  /// qq:116149 
  /// </summary> 
  public class POP3
  {
  private string m_Address = "pop.gmail.com";

  private int m_Port = 995;

  public POP3(string p_Address, int p_Port)
  {
  m_Address = p_Address;
  m_Port = p_Port;
  }

  /// <summary> 
  /// 获取Mail列表 
  /// </summary> 
  /// <param name="p_Name">用户名</param> 
  /// <param name="p_PassWord">密码</param> 
  /// <returns>Mail信息</returns> 
  public DataTable GetMailTable(string p_Name, string p_PassWord)
  {
  POP3Client _Client = new POP3Client();
  _Client.UserName = p_Name;
  _Client.PassWord = p_PassWord;
  _Client.Client = new TcpClient();
  _Client.Client.BeginConnect(m_Address, m_Port, new AsyncCallback(OnConnectRequest), _Client);
  while (!_Client.ReturnEnd)
  {
  System.Windows.Forms.Application.DoEvents();
  }
  if (_Client.Error.Length != 0) 
  throw new Exception("错误信息!" + _Client.Error);
  return _Client.MailDataTable;
  }


  /// <summary> 
  /// 获取邮件内容 
  /// </summary> 
  /// <param name="p_Name">名称</param> 
  /// <param name="p_PassWord">密码</param> 
  /// <param name="p_MailIndex">邮件编号</param> 
  /// <returns>数据集</returns> 
  public DataTable GetMail(string p_Name, string p_PassWord, int p_MailIndex)
  {
  POP3Client _Client = new POP3Client();
  _Client.UserName = p_Name;
  _Client.PassWord = p_PassWord;
  _Client.Client = new TcpClient();
  _Client.ReadIndex = p_MailIndex;
  _Client.Client.BeginConnect(m_Address, m_Port, new AsyncCallback(OnConnectRequest), _Client);
  while (!_Client.ReturnEnd)
  {
  System.Windows.Forms.Application.DoEvents();
  }
  if (_Client.Error.Length != 0) throw new Exception("错误信息!" + _Client.Error);
  return _Client.MailTable;
  }

  private class POP3Client
  {
  public TcpClient Client;

  public string UserName = "";

  public string PassWord = "";

  public bool ReturnEnd = false;

  public DataTable MailDataTable = new DataTable();

  public DataTable MailTable = new DataTable();

  public string Error = "";

  public bool ReadEnd = false;

  public int ReadIndex = -1;


  public POP3Client()
  {
  MailDataTable.Columns.Add("NUM");
  MailDataTable.Columns.Add("Size");
  MailDataTable.Columns.Add("Form");
  MailDataTable.Columns.Add("To");
  MailDataTable.Columns.Add("Subject");
  MailDataTable.Columns.Add("Date");

  MailTable.Columns.Add("Type", typeof(string));
  MailTable.Columns.Add("Text", typeof(object));
  MailTable.Columns.Add("Name", typeof(string));
  }

  private int m_SendMessage = 0;
  private int m_TOPIndex = 1;

  /// <summary> 
  /// 获取下一个登陆到获取列表需要(的)命令 
  /// </summary> 
  /// <param name="p_Value"></param> 
  /// <returns></returns> 
  public byte[] GetSendBytes(byte[] p_Value)
  {
  ReadEnd = false;
  string _Value = System.Text.Encoding.Default.GetString(p_Value).Replace("\0", "");
  if (_Value.IndexOf("+OK") == 0)
  {
  m_SendMessage++;
  switch (m_SendMessage)
  {
  case 1:
  return System.Text.Encoding.ASCII.GetBytes("USER " + UserName + "\r\n");
  case 2:
  return System.Text.Encoding.ASCII.GetBytes("PASS " + PassWord + "\r\n");
  case 3:
  ReadEnd = true;
  if (ReadIndex != -1)
  {
  m_SendMessage = 5;
  return System.Text.Encoding.ASCII.GetBytes("RETR " + ReadIndex.ToString() + "\r\n");
  }
  else
  {
  return System.Text.Encoding.ASCII.GetBytes("LIST\r\n");
  }
  case 4:
  string[] _List = _Value.Split(new char[] { '\r', '\n', '.' }, StringSplitOptions.RemoveEmptyEntries);
  for (int i = 1; i != _List.Length; i++)
  {
  string[] _MaliSize = _List[i].Split(' ');
  MailDataTable.Rows.Add(new object[] { _MaliSize[0], _MaliSize[1] });
  }
  if (MailDataTable.Rows.Count == 0)
  {
  ReturnEnd = true;
  return new byte[0];
  }
  else
  {
  ReadEnd = true;
  m_TOPIndex = 1;
  return System.Text.Encoding.ASCII.GetBytes("TOP 1\r\n");
  }
  case 5:
  System.Text.RegularExpressions.Regex _Regex = new System.Text.RegularExpressions.Regex(@"(?<=Date: ).*?(\r\n)+");
  System.Text.RegularExpressions.MatchCollection _Collection = _Regex.Matches(_Value);
  if (_Collection.Count != 0) MailDataTable.Rows[m_TOPIndex - 1]["Date"] = GetReadText(_Collection[0].Value);

  System.Text.RegularExpressions.Regex _RegexFrom = new System.Text.RegularExpressions.Regex(@"(?<=From: ).*?(\r\n)+");
  System.Text.RegularExpressions.MatchCollection _CollectionForm = _RegexFrom.Matches(_Value);
  if (_CollectionForm.Count != 0) MailDataTable.Rows[m_TOPIndex - 1]["Form"] = GetReadText(_CollectionForm[0].Value);


  System.Text.RegularExpressions.Regex _RegexTo = new System.Text.RegularExpressions.Regex(@"(?<=To: ).*?(\r\n)+");
  System.Text.RegularExpressions.MatchCollection _CollectionTo = _RegexTo.Matches(_Value);
  if (_CollectionTo.Count != 0) MailDataTable.Rows[m_TOPIndex - 1]["To"] = GetReadText(_CollectionTo[0].Value);

  System.Text.RegularExpressions.Regex _RegexSubject = new System.Text.RegularExpressions.Regex(@"(?<=Subject: ).*?(\r\n)+");
  System.Text.RegularExpressions.MatchCollection _CollectionSubject = _RegexSubject.Matches(_Value);
  if (_CollectionSubject.Count != 0) MailDataTable.Rows[m_TOPIndex - 1]["Subject"] = GetReadText(_CollectionSubject[0].Value);

  m_TOPIndex++;
  m_SendMessage--;
  ReadEnd = true;
  if (m_TOPIndex > MailDataTable.Rows.Count)
  {
  ReturnEnd = true;
  return System.Text.Encoding.ASCII.GetBytes("QUIT");
  }
  else
  {
  return System.Text.Encoding.ASCII.GetBytes("TOP " + m_TOPIndex.ToString() + "\r\n");
  }
  case 6:
  GetMailText(_Value);
  ReturnEnd = true;
  return System.Text.Encoding.ASCII.GetBytes("QUIT");

  }
  }
  Error = _Value;
  ReturnEnd = true;
  return new byte[0];
  }

  /// <summary> 
  /// 转换文字里(的)字符集 
  /// </summary> 
  /// <param name="p_Text"></param> 
  /// <returns></returns> 
  public string GetReadText(string p_Text)
  {
  System.Text.RegularExpressions.Regex _Regex = new System.Text.RegularExpressions.Regex(@"(?<=\=\?).*?(\?\=)+");
  System.Text.RegularExpressions.MatchCollection _Collection = _Regex.Matches(p_Text);
  string _Text = p_Text;
  foreach (System.Text.RegularExpressions.Match _Match in _Collection)
  {
  string _Value = "=?" + _Match.Value;
  if (_Value[0] == '=')
  {
  string[] _BaseData = _Value.Split('?');
  if (_BaseData.Length == 5)
  {
  System.Text.Encoding _Coding = System.Text.Encoding.GetEncoding(_BaseData[1]);
  _Text = _Text.Replace(_Value, _Coding.GetString(Convert.FromBase64String(_BaseData[3])));
  }
  }
  else
  {
  }
  }
  return _Text;
  }


 #region 获取邮件正文 和 附件
  /// <summary> 
  /// 获取文字主体 
  /// </summary> 
  /// <param name="p_Mail"></param> 
  /// <returns></returns> 
  public void GetMailText(string p_Mail)
  {
  string _ConvertType = GetTextType(p_Mail, "\r\nContent-Type: ", ";");
  if (_ConvertType.Length == 0)
  {
  _ConvertType = GetTextType(p_Mail, "\r\nContent-Type: ", "\r");
  }
  int _StarIndex = -1;
  int _EndIndex = -1;
  string _ReturnText = "";
  string _Transfer = "";
  string _Boundary = "";
  string _EncodingName = GetTextType(p_Mail, "charset=\"", "\"").Replace("\"", "");
  System.Text.Encoding _Encoding = System.Text.Encoding.Default;
  if (_EncodingName != "") _Encoding = System.Text.Encoding.GetEncoding(_EncodingName);
  switch (_ConvertType)
  {
  case "text/html;":
  _Transfer = GetTextType(p_Mail, "\r\nContent-Transfer-Encoding: ", "\r\n").Trim();
  _StarIndex = p_Mail.IndexOf("\r\n\r\n");
  if (_StarIndex != -1) _ReturnText = p_Mail.Substring(_StarIndex, p_Mail.Length - _StarIndex);
  switch (_Transfer)
  {
  case "8bit":

  break;
  case "quoted-printable":
  _ReturnText = DecodeQuotedPrintable(_ReturnText, _Encoding);
  break;
  case "base64":
  _ReturnText = DecodeBase64(_ReturnText, _Encoding);
  break;
  }
  MailTable.Rows.Add(new object[] { "text/html", _ReturnText });
  break;
  case "text/plain;":
  _Transfer = GetTextType(p_Mail, "\r\nContent-Transfer-Encoding: ", "\r\n").Trim();
  _StarIndex = p_Mail.IndexOf("\r\n\r\n");
  if (_StarIndex != -1) _ReturnText = p_Mail.Substring(_StarIndex, p_Mail.Length - _StarIndex);
  switch (_Transfer)
  {
  case "8bit":

  break;
  case "quoted-printable":
  _ReturnText = DecodeQuotedPrintable(_ReturnText, _Encoding);
  break;
  case "base64":
  _ReturnText = DecodeBase64(_ReturnText, _Encoding);
  break;
  }
  MailTable.Rows.Add(new object[] { "text/plain", _ReturnText });
  break;
  case "multipart/alternative;":
  _Boundary = GetTextType(p_Mail, "boundary=\"", "\"").Replace("\"", "");
  _StarIndex = p_Mail.IndexOf("--" + _Boundary + "\r\n");
  if (_StarIndex == -1) return;
  while (true)
  {
  _EndIndex = p_Mail.IndexOf("--" + _Boundary, _StarIndex + _Boundary.Length);
  if (_EndIndex == -1) break;
  GetMailText(p_Mail.Substring(_StarIndex, _EndIndex - _StarIndex));
  _StarIndex = _EndIndex;
  }
  break;
  case "multipart/mixed;":
  _Boundary = GetTextType(p_Mail, "boundary=\"", "\"").Replace("\"", "");
  _StarIndex = p_Mail.IndexOf("--" + _Boundary + "\r\n");
  if (_StarIndex == -1) return;
  while (true)
  {
  _EndIndex = p_Mail.IndexOf("--" + _Boundary, _StarIndex + _Boundary.Length);
  if (_EndIndex == -1) break;
  GetMailText(p_Mail.Substring(_StarIndex, _EndIndex - _StarIndex));
  _StarIndex = _EndIndex;
  }
  break;
  default:
  if (_ConvertType.IndexOf("application/") == 0)
  {
  _StarIndex = p_Mail.IndexOf("\r\n\r\n");
  if (_StarIndex != -1) _ReturnText = p_Mail.Substring(_StarIndex, p_Mail.Length - _StarIndex);
  _Transfer = GetTextType(p_Mail, "\r\nContent-Transfer-Encoding: ", "\r\n").Trim();
  string _Name = GetTextType(p_Mail, "filename=\"", "\"").Replace("\"", "");
  _Name = GetReadText(_Name);
  byte[] _FileBytes = new byte[0];
  switch (_Transfer)
  {
  case "base64":
  _FileBytes = Convert.FromBase64String(_ReturnText);
  break;
  }
  MailTable.Rows.Add(new object[] { "application/octet-stream", _FileBytes, _Name });

  }
  break;
  }
  }

  /// <summary> 
  /// 获取类型（正则） 
  /// </summary> 
  /// <param name="p_Mail">原始文字</param> 
  /// <param name="p_TypeText">前文字</param> 
  /// <param name="p_End">结束文字</param> 
  /// <returns>符合(的)记录</returns> 
  public string GetTextType(string p_Mail, string p_TypeText, string p_End)
  {
  System.Text.RegularExpressions.Regex _Regex = new System.Text.RegularExpressions.Regex(@"(?<=" + p_TypeText + ").*?(" + p_End + ")+");
  System.Text.RegularExpressions.MatchCollection _Collection = _Regex.Matches(p_Mail);
  if (_Collection.Count == 0) return "";
  return _Collection[0].Value;
  }

  /// <summary> 
  /// QuotedPrintable编码接码 
  /// </summary> 
  /// <param name="p_Text">原始文字</param> 
  /// <param name="p_Encoding">编码方式</param> 
  /// <returns>接码后信息</returns> 
  public string DecodeQuotedPrintable(string p_Text, System.Text.Encoding p_Encoding)
  {
  System.IO.MemoryStream _Stream = new System.IO.MemoryStream();
  char[] _CharValue = p_Text.ToCharArray();
  for (int i = 0; i != _CharValue.Length; i++)
  {
  switch (_CharValue[i])
  {
  case '=':
  if (_CharValue[i + 1] == '\r' || _CharValue[i + 1] == '\n')
  {
  i += 2;
  }
  else
  {
  try
  {
  _Stream.WriteByte(Convert.ToByte(_CharValue[i + 1].ToString() + _CharValue[i + 2].ToString(), 16));
  i += 2;
  }
  catch
  {
  _Stream.WriteByte(Convert.ToByte(_CharValue[i]));
  }
  }
  break;
  default:
  _Stream.WriteByte(Convert.ToByte(_CharValue[i]));
  break;
  }
  }
  return p_Encoding.GetString(_Stream.ToArray());
  }

  /// <summary> 
  /// 解码BASE64 
  /// </summary> 
  /// <param name="p_Text"></param> 
  /// <param name="p_Encoding"></param> 
  /// <returns></returns> 
  public string DecodeBase64(string p_Text, System.Text.Encoding p_Encoding)
  {
  if (p_Text.Trim().Length == 0) return "";
  byte[] _ValueBytes = Convert.FromBase64String(p_Text);
  return p_Encoding.GetString(_ValueBytes);
  }
  #endregion


  }

  /// <summary> 
  /// 连接事件 
  /// </summary> 
  /// <param name="ar"></param> 
  private void OnConnectRequest(IAsyncResult ar)
  {
  POP3Client _Client = (POP3Client)ar.AsyncState;
  byte[] _ReadBytes = new byte[0];
  _Client.Client.Client.BeginReceive(_ReadBytes, 0, 0, SocketFlags.None, new AsyncCallback(OnWrite), _Client);
  }

  /// <summary> 
  /// 连接事件 
  /// </summary> 
  /// <param name="ar"></param> 
  private void OnSend(IAsyncResult ar)
  {
  POP3Client _Client = (POP3Client)ar.AsyncState;
  byte[] _ReadBytes = new byte[0];
  _Client.Client.Client.BeginReceive(_ReadBytes, 0, 0, SocketFlags.None, new AsyncCallback(OnWrite), _Client);
  }

  /// <summary> 
  /// 连接事件 
  /// </summary> 
  /// <param name="ar"></param> 
  private void OnWrite(IAsyncResult ar)
  {
  POP3Client _Client = (POP3Client)ar.AsyncState;
  byte[] _WriteBytes = new byte[_Client.Client.Client.ReceiveBufferSize];
  _Client.Client.Client.Receive(_WriteBytes);
  if (_Client.ReadEnd) _WriteBytes = ReadEnd(_WriteBytes, _Client);
  byte[] _SendBytes = _Client.GetSendBytes(_WriteBytes);
  if (_SendBytes.Length == 0) return;
  _Client.Client.Client.BeginSend(_SendBytes, 0, _SendBytes.Length, SocketFlags.None, new AsyncCallback(OnSend), _Client);
  }

  /// <summary> 
  /// 获取知道获取到. 否则一直获取数据 
  /// </summary> 
  /// <param name="p_Value"></param> 
  /// <returns></returns> 
  private byte[] ReadEnd(byte[] p_Value, POP3Client p_Client)
  {
  if (System.Text.Encoding.ASCII.GetString(p_Value).IndexOf("\r\n.\r\n") != -1) return p_Value;
  MemoryStream _Stream = new MemoryStream();
  _Stream.Write(p_Value, 0, p_Value.Length);
  while (true)
  {
  byte[] _WriteBytes = new byte[p_Client.Client.ReceiveBufferSize];
  p_Client.Client.Client.Receive(_WriteBytes);
  _Stream.Write(_WriteBytes, 0, _WriteBytes.Length);
  System.Threading.Thread.Sleep(100);
  if (System.Text.Encoding.ASCII.GetString(_WriteBytes).IndexOf("\r\n.\r\n") != -1) return _Stream.ToArray();
  }
  }

  }
}