首页 > 代码库 > SmtpServerHelper
SmtpServerHelper
using System;
using System.Text;
using System.IO;
using System.Net.Sockets;
using System.Collections;
public enum MailFormat { Text, HTML };
public enum MailPriority { Low = 1, Normal = 3, High = 5 };
/// <summary>
/// 添加附件
/// </summary>
public class MailAttachments
{
#region 构造函数
public MailAttachments()
{
_Attachments = new ArrayList();
}
#endregion
#region 私有字段
private IList _Attachments;
private const int MaxAttachmentNum = 10;
#endregion
#region 索引器
public string this[int index]
{
get { return (string)_Attachments[index]; }
}
#endregion
#region 公共方法
/// <summary>
/// 添加邮件附件
/// </summary>
/// <param name="FilePath">附件的绝对路径</param>
public void Add(params string[] filePath)
{
if (filePath == null)
{
throw (new ArgumentNullException("非法的附件"));
}
else
{
for (int i = 0; i < filePath.Length; i++)
{
Add(filePath[i]);
}
}
}
/// <summary>
/// 添加一个附件,当指定的附件不存在时，忽略该附件，不产生异常。
/// </summary>
/// <param name="filePath">附件的绝对路径</param>
public void Add(string filePath)
{
if (System.IO.File.Exists(filePath))
{
if (_Attachments.Count < MaxAttachmentNum)
{
_Attachments.Add(filePath);
}
}
}
/// <summary>
/// 清除所有附件
/// </summary>
public void Clear()
{
_Attachments.Clear();
}
/// <summary>
/// 获取附件个数
/// </summary>
public int Count
{
get { return _Attachments.Count; }
}
#endregion
}
/// <summary>
/// 邮件信息
/// </summary>
public class MailMessage
{
#region 构造函数
public MailMessage()
{
_Recipients = new ArrayList(); //收件人列表
_Attachments = new MailAttachments(); //附件
_BodyFormat = MailFormat.HTML; //缺省的邮件格式为HTML
_Priority = MailPriority.Normal;
_Charset = "GB2312";
}
#endregion
#region 私有字段
private int _MaxRecipientNum = 30;
private string _From; //发件人地址
private string _FromName; //发件人姓名
private IList _Recipients; //收件人
private MailAttachments _Attachments;//附件
private string _Body; //内容
private string _Subject; //主题
private MailFormat _BodyFormat; //邮件格式
private string _Charset = "GB2312"; //字符编码格式
private MailPriority _Priority; //邮件优先级
#endregion
#region 公有属性
/// <summary>
/// 设定语言代码，默认设定为GB2312，如不需要可设置为""
/// </summary>
public string Charset
{
get { return _Charset; }
set { _Charset = value; }
}
/// <summary>
/// 最大收件人
/// </summary>
public int MaxRecipientNum
{
get { return _MaxRecipientNum; }
set { _MaxRecipientNum = value; }
}
/// <summary>
/// 发件人地址
/// </summary>
public string From
{
get { return _From; }
set { _From = value; }
}
/// <summary>
/// 发件人姓名
/// </summary>
public string FromName
{
get { return _FromName; }
set { _FromName = value; }
}
/// <summary>
/// 内容
/// </summary>
public string Body
{
get { return _Body; }
set { _Body = value; }
}
/// <summary>
/// 主题
/// </summary>
public string Subject
{
get { return _Subject; }
set { _Subject = value; }
}
/// <summary>
/// 附件
/// </summary>
public MailAttachments Attachments
{
get { return _Attachments; }
set { _Attachments = value; }
}
/// <summary>
/// 优先权
/// </summary>
public MailPriority Priority
{
get { return _Priority; }
set { _Priority = value; }
}
/// <summary>
/// 收件人
/// </summary>
public IList Recipients
{
get { return _Recipients; }
}
/// <summary>
/// 邮件格式
/// </summary>
public MailFormat BodyFormat
{
set { _BodyFormat = value; }
get { return _BodyFormat; }
}
#endregion
#region 公共方法
/// <summary>
/// 增加一个收件人地址
/// </summary>
/// <param name="recipient">收件人的Email地址</param>
public void AddRecipients(string recipient)
{
if (_Recipients.Count < MaxRecipientNum)
{
_Recipients.Add(recipient);
}
}
/// <summary>
/// 增加多个收件人地址
/// </summary>
/// <param name="recipient">收件人的Email地址集合</param>
public void AddRecipients(params string[] recipient)
{
if (recipient == null)
{
throw (new ArgumentException("收件人不能为空."));
}
else
{
for (int i = 0; i < recipient.Length; i++)
{
AddRecipients(recipient[i]);
}
}
}
#endregion
}
/// <summary>
/// 邮件操作
/// </summary>
public class SmtpServerHelper
{
#region 构造函数、析构函数
public SmtpServerHelper()
{
SMTPCodeAdd();
}
~SmtpServerHelper()
{
networkStream.Close();
tcpClient.Close();
}
#endregion
#region 私有字段
/// <summary>
/// 回车换行
/// </summary>
private string CRLF = "\r\n";
/// <summary>
/// 错误消息反馈
/// </summary>
private string errmsg;
/// <summary>
/// TcpClient对象，用于连接服务器
/// </summary>
private TcpClient tcpClient;
/// <summary>
/// NetworkStream对象
/// </summary>
private NetworkStream networkStream;
/// <summary>
/// 服务器交互记录
/// </summary>
private string logs = "";
/// <summary>
/// SMTP错误代码哈希表
/// </summary>
private Hashtable ErrCodeHT = new Hashtable();
/// <summary>
/// SMTP正确代码哈希表
/// </summary>
private Hashtable RightCodeHT = new Hashtable();
#endregion
#region 公有属性
/// <summary>
/// 错误消息反馈
/// </summary>
public string ErrMsg
{
set { errmsg = value; }
get { return errmsg; }
}
#endregion
#region 私有方法
/// <summary>
/// 将字符串编码为Base64字符串
/// </summary>
/// <param name="str">要编码的字符串</param>
private string Base64Encode(string str)
{
byte[] barray;
barray = Encoding.Default.GetBytes(str);
return Convert.ToBase64String(barray);
}
/// <summary>
/// 将Base64字符串解码为普通字符串
/// </summary>
/// <param name="str">要解码的字符串</param>
private string Base64Decode(string str)
{
byte[] barray;
barray = Convert.FromBase64String(str);
return Encoding.Default.GetString(barray);
}
/// <summary>
/// 得到上传附件的文件流
/// </summary>
/// <param name="FilePath">附件的绝对路径</param>
private string GetStream(string FilePath)
{
System.IO.FileStream FileStr = new System.IO.FileStream(FilePath, System.IO.FileMode.Open);
byte[] by = new byte[System.Convert.ToInt32(FileStr.Length)];
FileStr.Read(by, 0, by.Length);
FileStr.Close();
return (System.Convert.ToBase64String(by));
}
/// <summary>
/// SMTP回应代码哈希表
/// </summary>
private void SMTPCodeAdd()
{
ErrCodeHT.Add("421", "服务未就绪，关闭传输信道");
ErrCodeHT.Add("432", "需要一个密码转换");
ErrCodeHT.Add("450", "要求的邮件操作未完成，邮箱不可用（例如，邮箱忙）");
ErrCodeHT.Add("451", "放弃要求的操作；处理过程中出错");
ErrCodeHT.Add("452", "系统存储不足，要求的操作未执行");
ErrCodeHT.Add("454", "临时认证失败");
ErrCodeHT.Add("500", "邮箱地址错误");
ErrCodeHT.Add("501", "参数格式错误");
ErrCodeHT.Add("502", "命令不可实现");
ErrCodeHT.Add("503", "服务器需要SMTP验证");
ErrCodeHT.Add("504", "命令参数不可实现");
ErrCodeHT.Add("530", "需要认证");
ErrCodeHT.Add("534", "认证机制过于简单");
ErrCodeHT.Add("538", "当前请求的认证机制需要加密");
ErrCodeHT.Add("550", "要求的邮件操作未完成，邮箱不可用（例如，邮箱未找到，或不可访问）");
ErrCodeHT.Add("551", "用户非本地，请尝试<forward-path>");
ErrCodeHT.Add("552", "过量的存储分配，要求的操作未执行");
ErrCodeHT.Add("553", "邮箱名不可用，要求的操作未执行（例如邮箱格式错误）");
ErrCodeHT.Add("554", "传输失败");
RightCodeHT.Add("220", "服务就绪");
RightCodeHT.Add("221", "服务关闭传输信道");
RightCodeHT.Add("235", "验证成功");
RightCodeHT.Add("250", "要求的邮件操作完成");
RightCodeHT.Add("251", "非本地用户，将转发向<forward-path>");
RightCodeHT.Add("334", "服务器响应验证Base64字符串");
RightCodeHT.Add("354", "开始邮件输入，以<CRLF>.<CRLF>结束");
}
/// <summary>
/// 发送SMTP命令
/// </summary>
private bool SendCommand(string str)
{
byte[] WriteBuffer;
if (str == null || str.Trim() == String.Empty)
{
return true;
}
logs += str;
WriteBuffer = Encoding.Default.GetBytes(str);
try
{
networkStream.Write(WriteBuffer, 0, WriteBuffer.Length);
}
catch
{
errmsg = "网络连接错误";
return false;
}
return true;
}
/// <summary>
/// 接收SMTP服务器回应
/// </summary>
private string RecvResponse()
{
int StreamSize;
string Returnvalue = http://www.mamicode.com/String.Empty;
byte[] ReadBuffer = new byte[1024];
try
{
StreamSize = networkStream.Read(ReadBuffer, 0, ReadBuffer.Length);
}
catch
{
errmsg = "网络连接错误";
return "false";
}
if (StreamSize == 0)
{
return Returnvalue;
}
else
{
Returnvalue = http://www.mamicode.com/Encoding.Default.GetString(ReadBuffer).Substring(0, StreamSize);
logs += Returnvalue + this.CRLF;
return Returnvalue;
}
}
/// <summary>
/// 与服务器交互，发送一条命令并接收回应。
/// </summary>
/// <param name="str">一个要发送的命令</param>
/// <param name="errstr">如果错误，要反馈的信息</param>
private bool Dialog(string str, string errstr)
{
if (str == null || str.Trim() == string.Empty)
{
return true;
}
if (SendCommand(str))
{
string RR = RecvResponse();
if (RR == "false")
{
return false;
}
//检查返回的代码，根据[RFC 821]返回代码为3位数字代码如220
string RRCode = RR.Substring(0, 3);
if (RightCodeHT[RRCode] != null)
{
return true;
}
else
{
if (ErrCodeHT[RRCode] != null)
{
errmsg += (RRCode + ErrCodeHT[RRCode].ToString());
errmsg += CRLF;
}
else
{
errmsg += RR;
}
errmsg += errstr;
return false;
}
}
else
{
return false;
}
}
/// <summary>
/// 与服务器交互，发送一组命令并接收回应。
/// </summary>
private bool Dialog(string[] str, string errstr)
{
for (int i = 0; i < str.Length; i++)
{
if (!Dialog(str[i], ""))
{
errmsg += CRLF;
errmsg += errstr;
return false;
}
}
return true;
}
/// <summary>
/// 连接服务器
/// </summary>
private bool Connect(string smtpServer, int port)
{
try
{
tcpClient = new TcpClient(smtpServer, port);
}
catch (Exception e)
{
errmsg = e.ToString();
return false;
}
networkStream = tcpClient.GetStream();
if (RightCodeHT[RecvResponse().Substring(0, 3)] == null)
{
errmsg = "网络连接失败";
return false;
}
return true;
}
/// <summary>
/// 获取优先级
/// </summary>
/// <param name="mailPriority">优先级</param>
private string GetPriorityString(MailPriority mailPriority)
{
string priority = "Normal";
if (mailPriority == MailPriority.Low)
{
priority = "Low";
}
else if (mailPriority == MailPriority.High)
{
priority = "High";
}
return priority;
}
/// <summary>
/// 发送电子邮件
/// </summary>
/// <param name="smtpServer">发信SMTP服务器</param>
/// <param name="port">端口，默认为25</param>
/// <param name="username">发信人邮箱地址</param>
/// <param name="password">发信人邮箱密码</param>
/// <param name="mailMessage">邮件内容</param>
private bool SendEmail(string smtpServer, int port, bool ESmtp, string username, string password, MailMessage mailMessage)
{
if (Connect(smtpServer, port) == false) return false;
string priority = GetPriorityString(mailMessage.Priority);
bool Html = (mailMessage.BodyFormat == MailFormat.HTML);
string[] SendBuffer;
string SendBufferstr;
//进行SMTP验证
if (ESmtp)
{
SendBuffer = new String[4];
SendBuffer[0] = "EHLO " + smtpServer + CRLF;
SendBuffer[1] = "AUTH LOGIN" + CRLF;
SendBuffer[2] = Base64Encode(username) + CRLF;
SendBuffer[3] = Base64Encode(password) + CRLF;
if (!Dialog(SendBuffer, "SMTP服务器验证失败，请核对用户名和密码。")) return false;
}
else
{
SendBufferstr = "HELO " + smtpServer + CRLF;
if (!Dialog(SendBufferstr, "")) return false;
}
//发件人地址
SendBufferstr = "MAIL FROM:<" + username + ">" + CRLF;
if (!Dialog(SendBufferstr, "发件人地址错误，或不能为空")) return false;
//收件人地址
SendBuffer = new string[mailMessage.Recipients.Count];
for (int i = 0; i < mailMessage.Recipients.Count; i++)
{
SendBuffer[i] = "RCPT TO:<" + (string)mailMessage.Recipients[i] + ">" + CRLF;
}
if (!Dialog(SendBuffer, "收件人地址有误")) return false;
SendBufferstr = "DATA" + CRLF;
if (!Dialog(SendBufferstr, "")) return false;
//发件人姓名
SendBufferstr = "From:" + mailMessage.FromName + "<" + mailMessage.From + ">" + CRLF;
if (mailMessage.Recipients.Count == 0)
{
return false;
}
else
{
SendBufferstr += "To:=?" + mailMessage.Charset.ToUpper() + "?B?" + Base64Encode((string)mailMessage.Recipients[0]) + "?=" + "<" + (string)mailMessage.Recipients[0] + ">" + CRLF;
}
SendBufferstr += ((mailMessage.Subject == String.Empty || mailMessage.Subject == null) ? "Subject:" : ((mailMessage.Charset == "") ? ("Subject:" + mailMessage.Subject) : ("Subject:" + "=?" + mailMessage.Charset.ToUpper() + "?B?" + Base64Encode(mailMessage.Subject) + "?="))) + CRLF;
SendBufferstr += "X-Priority:" + priority + CRLF;
SendBufferstr += "X-MSMail-Priority:" + priority + CRLF;
SendBufferstr += "Importance:" + priority + CRLF;
SendBufferstr += "X-Mailer: Lion.Web.Mail.SmtpMail Pubclass [cn]" + CRLF;
SendBufferstr += "MIME-Version: 1.0" + CRLF;
if (mailMessage.Attachments.Count != 0)
{
SendBufferstr += "Content-Type: multipart/mixed;" + CRLF;
SendBufferstr += " boundary=\"=====" + (Html ? "001_Dragon520636771063_" : "001_Dragon303406132050_") + "=====\"" + CRLF + CRLF;
}
if (Html)
{
if (mailMessage.Attachments.Count == 0)
{
SendBufferstr += "Content-Type: multipart/alternative;" + CRLF; //内容格式和分隔符
SendBufferstr += " boundary=\"=====003_Dragon520636771063_=====\"" + CRLF + CRLF;
SendBufferstr += "This is a multi-part message in MIME format." + CRLF + CRLF;
}
else
{
SendBufferstr += "This is a multi-part message in MIME format." + CRLF + CRLF;
SendBufferstr += "--=====001_Dragon520636771063_=====" + CRLF;
SendBufferstr += "Content-Type: multipart/alternative;" + CRLF; //内容格式和分隔符
SendBufferstr += " boundary=\"=====003_Dragon520636771063_=====\"" + CRLF + CRLF;
}
SendBufferstr += "--=====003_Dragon520636771063_=====" + CRLF;
SendBufferstr += "Content-Type: text/plain;" + CRLF;
SendBufferstr += ((mailMessage.Charset == "") ? (" charset=\"iso-8859-1\"") : (" charset=\"" + mailMessage.Charset.ToLower() + "\"")) + CRLF;
SendBufferstr += "Content-Transfer-Encoding: base64" + CRLF + CRLF;
SendBufferstr += Base64Encode("邮件内容为HTML格式，请选择HTML方式查看") + CRLF + CRLF;
SendBufferstr += "--=====003_Dragon520636771063_=====" + CRLF;
SendBufferstr += "Content-Type: text/html;" + CRLF;
SendBufferstr += ((mailMessage.Charset == "") ? (" charset=\"iso-8859-1\"") : (" charset=\"" + mailMessage.Charset.ToLower() + "\"")) + CRLF;
SendBufferstr += "Content-Transfer-Encoding: base64" + CRLF + CRLF;
SendBufferstr += Base64Encode(mailMessage.Body) + CRLF + CRLF;
SendBufferstr += "--=====003_Dragon520636771063_=====--" + CRLF;
}
else
{
if (mailMessage.Attachments.Count != 0)
{
SendBufferstr += "--=====001_Dragon303406132050_=====" + CRLF;
}
SendBufferstr += "Content-Type: text/plain;" + CRLF;
SendBufferstr += ((mailMessage.Charset == "") ? (" charset=\"iso-8859-1\"") : (" charset=\"" + mailMessage.Charset.ToLower() + "\"")) + CRLF;
SendBufferstr += "Content-Transfer-Encoding: base64" + CRLF + CRLF;
SendBufferstr += Base64Encode(mailMessage.Body) + CRLF;
}
if (mailMessage.Attachments.Count != 0)
{
for (int i = 0; i < mailMessage.Attachments.Count; i++)
{
string filepath = (string)mailMessage.Attachments[i];
SendBufferstr += "--=====" + (Html ? "001_Dragon520636771063_" : "001_Dragon303406132050_") + "=====" + CRLF;
SendBufferstr += "Content-Type: text/plain;" + CRLF;
SendBufferstr += " name=\"=?" + mailMessage.Charset.ToUpper() + "?B?" + Base64Encode(filepath.Substring(filepath.LastIndexOf("\\") + 1)) + "?=\"" + CRLF;
SendBufferstr += "Content-Transfer-Encoding: base64" + CRLF;
SendBufferstr += "Content-Disposition: attachment;" + CRLF;
SendBufferstr += " filename=\"=?" + mailMessage.Charset.ToUpper() + "?B?" + Base64Encode(filepath.Substring(filepath.LastIndexOf("\\") + 1)) + "?=\"" + CRLF + CRLF;
SendBufferstr += GetStream(filepath) + CRLF + CRLF;
}
SendBufferstr += "--=====" + (Html ? "001_Dragon520636771063_" : "001_Dragon303406132050_") + "=====--" + CRLF + CRLF;
}
SendBufferstr += CRLF + "." + CRLF;
if (!Dialog(SendBufferstr, "错误信件信息")) return false;
SendBufferstr = "QUIT" + CRLF;
if (!Dialog(SendBufferstr, "断开连接时错误")) return false;
networkStream.Close();
tcpClient.Close();
return true;
}
#endregion
#region 公有方法
/// <summary>
/// 发送电子邮件,SMTP服务器不需要身份验证
/// </summary>
/// <param name="smtpServer">发信SMTP服务器</param>
/// <param name="port">端口，默认为25</param>
/// <param name="mailMessage">邮件内容</param>
public bool SendEmail(string smtpServer, int port, MailMessage mailMessage)
{
return SendEmail(smtpServer, port, false, "", "", mailMessage);
}
/// <summary>
/// 发送电子邮件,SMTP服务器需要身份验证
/// </summary>
/// <param name="smtpServer">发信SMTP服务器</param>
/// <param name="port">端口，默认为25</param>
/// <param name="username">发信人邮箱地址</param>
/// <param name="password">发信人邮箱密码</param>
/// <param name="mailMessage">邮件内容</param>
public bool SendEmail(string smtpServer, int port, string username, string password, MailMessage mailMessage)
{
return SendEmail(smtpServer, port, true, username, password, mailMessage);
}
#endregion
}
/// <summary>
/// 发送邮件
/// </summary>
//--------------------调用-----------------------
//MailAttachments ma=new MailAttachments();
//ma.Add(@"附件地址");
//MailMessage mail = new MailMessage();
//mail.Attachments=ma;
//mail.Body="你好";
//mail.AddRecipients("zjy99684268@163.com");
//mail.From="zjy99684268@163.com";
//mail.FromName="zjy";
//mail.Subject="Hello";
//SmtpClient sp = new SmtpClient();
//sp.SmtpServer = "smtp.163.com";
//sp.Send(mail, "zjy99684268@163.com", "123456");
//------------------------------------------------
public class SmtpClient
{
#region 构造函数
public SmtpClient()
{}
public SmtpClient(string _smtpServer)
{
_SmtpServer = _smtpServer;
}
#endregion
#region 私有字段
private string errmsg;
private string _SmtpServer;
#endregion
#region 公有属性
/// <summary>
/// 错误消息反馈
/// </summary>
public string ErrMsg
{
get { return errmsg; }
}
/// <summary>
/// 邮件服务器
/// </summary>
public string SmtpServer
{
set { _SmtpServer = value; }
get { return _SmtpServer; }
}
#endregion
public bool Send(MailMessage mailMessage, string username, string password)
{
SmtpServerHelper helper = new SmtpServerHelper();
if (helper.SendEmail(_SmtpServer, 25, username, password, mailMessage))
return true;
else
{
errmsg = helper.ErrMsg;
return false;
}
}
}
/// <summary>
/// 操作服务器上邮件
/// </summary>
public class SmtpMail
{
public SmtpMail()
{ }
#region 字段
private StreamReader sr;
private StreamWriter sw;
private TcpClient tcpClient;
private NetworkStream networkStream;
#endregion
#region 私有方法
/// <summary>
/// 向服务器发送信息
/// </summary>
private bool SendDataToServer(string str)
{
try
{
sw.WriteLine(str);
sw.Flush();
return true;
}
catch (Exception err)
{
return false;
}
}
/// <summary>
/// 从网络流中读取服务器回送的信息
/// </summary>
private string ReadDataFromServer()
{
string str = null;
try
{
str = sr.ReadLine();
if (str[0] == ‘-‘)
{
str = null;
}
}
catch (Exception err)
{
str = err.Message;
}
return str;
}
#endregion
#region 获取邮件信息
/// <summary>
/// 获取邮件信息
/// </summary>
/// <param name="uid">邮箱账号</param>
/// <param name="pwd">邮箱密码</param>
/// <returns>邮件信息</returns>
public ArrayList ReceiveMail(string uid, string pwd)
{
ArrayList EmailMes = new ArrayList();
string str;
int index = uid.IndexOf(‘@‘);
string pop3Server = "pop3." + uid.Substring(index + 1);
tcpClient = new TcpClient(pop3Server, 110);
networkStream = tcpClient.GetStream();
sr = new StreamReader(networkStream);
sw = new StreamWriter(networkStream);
if (ReadDataFromServer() == null) return EmailMes;
if (SendDataToServer("USER " + uid) == false) return EmailMes;
if (ReadDataFromServer() == null) return EmailMes;
if (SendDataToServer("PASS " + pwd) == false) return EmailMes;
if (ReadDataFromServer() == null) return EmailMes;
if (SendDataToServer("LIST") == false) return EmailMes;
if ((str = ReadDataFromServer()) == null) return EmailMes;
string[] splitString = str.Split(‘ ‘);
int count = int.Parse(splitString[1]);
if (count > 0)
{
for (int i = 0; i < count; i++)
{
if ((str = ReadDataFromServer()) == null) return EmailMes;
splitString = str.Split(‘ ‘);
EmailMes.Add(string.Format("第{0}封邮件，{1}字节", splitString[0], splitString[1]));
}
return EmailMes;
}
else
{
return EmailMes;
}
}
#endregion
#region 读取邮件内容
/// <summary>
/// 读取邮件内容
/// </summary>
/// <param name="mailMessage">第几封</param>
/// <returns>内容</returns>
public string ReadEmail(string str)
{
string state = "";
if (SendDataToServer("RETR " + str) == false)
state = "Error";
else
{
state = sr.ReadToEnd();
}
return state;
}
#endregion
#region 删除邮件
/// <summary>
/// 删除邮件
/// </summary>
/// <param name="str">第几封</param>
/// <returns>操作信息</returns>
public string DeleteEmail(string str)
{
string state = "";
if (SendDataToServer("DELE " + str) == true)
{
state = "成功删除";
}
else
{
state = "Error";
}
return state;
}
#endregion
#region 关闭服务器连接
/// <summary>
/// 关闭服务器连接
/// </summary>
public void CloseConnection()
{
SendDataToServer("QUIT");
sr.Close();
sw.Close();
networkStream.Close();
tcpClient.Close();
}
#endregion
}
SmtpServerHelper