通用类 SmtpHelper 邮件附件

public enum MailFormat { Text, HTML };
public enum MailPriority { Low = 1, Normal = 3, High = 5 };
 
#region Class mailAttachments
public class MailAttachments
{
    private const int MaxAttachmentNum = 10;
    private IList _Attachments;
 
    public MailAttachments()
    {
        _Attachments = new ArrayList();
    }
 
    public string this[int index]
    {
        get { return (string)_Attachments[index]; }
    }
    /// <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)
    {
        //当附件存在时才加入,否则忽略
        if (System.IO.File.Exists(filePath))
        {
            if (_Attachments.Count < MaxAttachmentNum)
            {
                _Attachments.Add(filePath);
            }
        }
    }
 
    public void Clear()//清除所有附件
    {
        _Attachments.Clear();
    }
 
    public int Count//获取附件个数
    {
        get { return _Attachments.Count; }
    }
 
}
#endregion//end Class mailAttachments
 
#region Class MailMessage
/// <summary>
/// MailMessage 表示SMTP要发送的一封邮件的消息。
/// </summary>
public class MailMessage
{
    private const int MaxRecipientNum = 10;
    public MailMessage()
    {
        _Recipients = new ArrayList();//收件人列表
        _Attachments = new MailAttachments();//附件
        _BodyFormat = MailFormat.Text;//缺省的邮件格式为Text
        _Priority = MailPriority.Normal;
        _Charset = "UTF-8";
    }
 
    /// <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; }
    }
 
    public string From
    {
        get { return _From; }
        set { _From = value; }
    }
 
    public string FromName
    {
        get { return _FromName; }
        set { _FromName = value; }
    }
    public string Body
    {
        get { return _Body; }
        set { _Body = value; }
    }
 
    public string Subject
    {
        get { return _Subject; }
        set { _Subject = value; }
    }
 
    public MailAttachments Attachments
    {
        get { return _Attachments; }
        set { _Attachments = value; }
    }
 
    public MailPriority Priority
    {
        get { return _Priority; }
        set { _Priority = value; }
    }
 
    public IList Recipients
    {
        get { return _Recipients; }
    }
    /// <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)
    {
        //先检查邮件地址是否符合规范
        if (_Recipients.Count < MaxRecipientNum)
        {
            _Recipients.Add(recipient);//增加到收件人列表
        }
    }
 
    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]);
            }
        }
    }
 
    public MailFormat BodyFormat
    {
        set { _BodyFormat = value; }
        get { return _BodyFormat; }
    }
 
    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 Class SmtpMail
public class SmtpServerHelper
{
    private string CRLF = "\r\n";//回车换行
 
    /// <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();
 
    public SmtpServerHelper()
    {
        SMTPCodeAdd();//初始化SMTPCode
    }
 
    ~SmtpServerHelper()
    {
        networkStream.Close();
        tcpClient.Close();
    }
 
    /// <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)
    {
        //建立文件流对象
        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()
    {
        //[RFC 821 4.2.1.]
        /*
          4.2.2.  NUMERIC ORDER LIST OF REPLY CODES
 
        211 System status, or system help reply
        214 Help message
           [Information on how to use the receiver or the meaning of a
           particular non-standard command; this reply is useful only
           to the human user]
        220 <domain> Service ready
        221 <domain> Service closing transmission channel
        250 Requested mail action okay, completed
        251 User not local; will forward to <forward-path>
      
        354 Start mail input; end with <CRLF>.<CRLF>
      
        421 <domain> Service not available,
         closing transmission channel
           [This may be a reply to any command if the service knows it
           must shut down]
        450 Requested mail action not taken: mailbox unavailable
           [E.g., mailbox busy]
        451 Requested action aborted: local error in processing
        452 Requested action not taken: insufficient system storage
      
        500 Syntax error, command unrecognized
           [This may include errors such as command line too long]
        501 Syntax error in parameters or arguments
        502 Command not implemented
        503 Bad sequence of commands
        504 Command parameter not implemented
        550 Requested action not taken: mailbox unavailable
           [E.g., mailbox not found, no access]
        551 User not local; please try <forward-path>
        552 Requested mail action aborted: exceeded storage allocation
        553 Requested action not taken: mailbox name not allowed
           [E.g., mailbox syntax incorrect]
        554 Transaction failed
 
        */
 
        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");
 
 
        /*
        211 System status, or system help reply
        214 Help message
           [Information on how to use the receiver or the meaning of a
           particular non-standard command; this reply is useful only
           to the human user]
        220 <domain> Service ready
        221 <domain> Service closing transmission channel
        250 Requested mail action okay, completed
        251 User not local; will forward to <forward-path>
      
        354 Start mail input; end with <CRLF>.<CRLF>
        */
 
        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 = 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 = 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;
    }
 
 
    //连接服务器
    private bool Connect(string smtpServer, int port)
    {
        //创建Tcp连接
        try
        {
            tcpClient = new TcpClient(smtpServer, port);
        }
        catch (Exception e)
        {
            errmsg = e.ToString();
            return false;
        }
        networkStream = tcpClient.GetStream();
 
        //验证网络连接是否正确
        if (RightCodeHT[RecvResponse().Substring(0, 3)] == null)
        {
            errmsg = "网络连接失败";
            return false;
        }
        return true;
    }
 
    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,SMTP服务器不需要身份验证
    /// </summary>
    /// <param name="smtpServer"></param>
    /// <param name="port"></param>
    /// <param name="mailMessage"></param>
    /// <returns></returns>
    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"></param>
    /// <param name="port"></param>
    /// <param name="username"></param>
    /// <param name="password"></param>
    /// <param name="mailMessage"></param>
    /// <returns></returns>
    public bool SendEmail(string smtpServer, int port, string username, string password, MailMessage mailMessage)
    {
        return SendEmail(smtpServer, port, false, username, password, mailMessage);
    }
 
    private bool SendEmail(string smtpServer, int port, bool ESmtp, string username, string password, MailMessage mailMessage)
    {
        if (Connect(smtpServer, port) == false)//测试连接服务器是否成功
            return false;
 
        string priority = GetPriorityString(mailMessage.Priority);
        bool Html = (mailMessage.BodyFormat == MailFormat.HTML);
 
        string[] SendBuffer;
        string SendBufferstr;
 
        //进行SMTP验证,现在大部分SMTP服务器都要认证
        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
        {//不需要身份认证
            SendBufferstr = "HELO " + smtpServer + CRLF;
            if (!Dialog(SendBufferstr, ""))
                return false;
        }
 
        //发件人地址
        SendBufferstr = "MAIL FROM:<" + mailMessage.From + ">" + 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;
 
        /*
          SendBuffer=new string[10];
          for(int i=0;i<RecipientBCC.Count;i++)
          {
 
        SendBuffer[i]="RCPT TO:<" + RecipientBCC[i].ToString() +">" + CRLF;
 
          }
 
          if(!Dialog(SendBuffer,"密件收件人地址有误"))
        return false;
        */
 
        SendBufferstr = "DATA" + CRLF;
        if (!Dialog(SendBufferstr, ""))
            return false;
 
        //发件人姓名
        SendBufferstr = "From:" + mailMessage.FromName + "<" + mailMessage.From + ">" + CRLF;
 
        //if(ReplyTo.Trim()!="")
        //{
        // SendBufferstr+="Reply-To: " + ReplyTo + CRLF;
        //}
 
        //SendBufferstr+="To:" + ToName + "<" + Recipient[0] +">" +CRLF;
        //至少要有一个收件人
        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+="CC:";
        //for(int i=0;i<Recipient.Count;i++)
        //{
        // SendBufferstr+=Recipient[i].ToString() + "<" + Recipient[i].ToString() +">,";
        //}
        //SendBufferstr+=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;
        }
 
        //SendBufferstr += "Content-Transfer-Encoding: base64"+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: application/octet-stream"+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;//内容结束
 
        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;
    }
}
 
public class SmtpMail
{
    private static string _SmtpServer;
 
    /// <summary>
    /// 格式:SmtpAccount:Password@SmtpServerAddress<br>
    /// 或者:SmtpServerAddress<br>
    /// <code>
    /// SmtpMail.SmtpServer="user:12345678@smtp.126.com";
    /// //或者:
    /// SmtpMail.SmtpServer="smtp.126.com";
    /// 或者:
    /// SmtpMail.SmtpServer=SmtpServerHelper.GetSmtpServer("user","12345678","smtp.126.com");
    /// </code>
    /// </summary>
    public static string SmtpServer
    {
        set { _SmtpServer = value; }
        get { return _SmtpServer; }
    }
 
    public static bool Send(MailMessage mailMessage, string username, string password)
    {
        SmtpServerHelper helper = new SmtpServerHelper();
        return helper.SendEmail(_SmtpServer, 25, username, password, mailMessage);
    }
 
}
 
#endregion

 

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