.net 接收邮件

方法一

using System;
using System.Net;
using System.Net.Mail;
using System.Net.Mime;
using System.Threading;
using System.Net.Sockets;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Net.Configuration;
using System.Configuration;

    #region 邮件接收类

    /// <summary>
    /// 邮件接收类
    /// </summary>
    public class POP3
    {
        #region Fields

        string POPServer;
        string mPOPUserName;
        string mPOPPass;
        int mPOPPort;
        NetworkStream ns;
        StreamReader sr;

        #endregion

        #region Constructors

        /// <summary>
        /// POP3
        /// </summary>
        /// <param name="server">POP3服务器名称 </param>
        /// <param name="userName">用户名 </param>
        /// <param name="password">用户密码 </param>
        public POP3(string server, string userName, string password)
            : this(server, 110, userName, password)
        {
        }

        /// <summary>
        /// POP3
        /// </summary>
        /// <param name="server">POP3服务器名称 </param>
        /// <param name="port">端口号 </param>
        /// <param name="userName">用户名 </param>
        /// <param name="password">用户密码 </param>
        public POP3(string server, int port, string userName, string password)
        {
            POPServer = server;
            mPOPUserName = userName;
            mPOPPass = password;
            mPOPPort = port;
        }

        #endregion

        #region Methods

        #region Public

        /// <summary>
        /// 获得新邮件数量
        /// </summary>
        /// <returns>新邮件数量 </returns>
        public int GetNumberOfNewMessages()
        {
            byte[] outbytes;
            string input;

            try
            {
                Connect();

                input = "stat" + "\r\n";
                outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
                ns.Write(outbytes, 0, outbytes.Length);
                string resp = sr.ReadLine();
                string[] tokens = resp.Split(new Char[] { ' ' });

                Disconnect();

                return Convert.ToInt32(tokens[1]);
            }
            catch
            {
                return -1;
            }
        }

        /// <summary>
        /// 获取新邮件内容
        /// </summary>
        /// <param name="subj">邮件主题 </param>
        /// <returns>新邮件内容 </returns>
        public List <MailMessage> GetNewMessages(string subj)
        {

            int newcount;
            List <MailMessage> newmsgs = new List <MailMessage>();

            try
            {
                newcount = GetNumberOfNewMessages();
                Connect();

                for (int n = 1; n < newcount + 1; n++)
                {
                    List <string> msglines = GetRawMessage(n);
                    string msgsubj = GetMessageSubject(msglines);
                    if (msgsubj.CompareTo(subj) == 0)
                    {
                        MailMessage msg = new MailMessage();
                        msg.Subject = msgsubj;
                        msg.From = new MailAddress(GetMessageFrom(msglines));
                        msg.Body = GetMessageBody(msglines);
                        newmsgs.Add(msg);
                        DeleteMessage(n);
                    }
                }

                Disconnect();
                return newmsgs;
            }
            catch (Exception e)
            {
                return newmsgs;
            }
        }

  
 /// <summary>
        /// 获取新邮件内容
        /// </summary>
        /// <param name="nIndex">新邮件索引 </param>
        /// <returns>新邮件内容 </returns>
        public MailMessage GetNewMessages(int nIndex)
        {
            int newcount;
            MailMessage msg = new MailMessage();

            try
            {
                newcount = GetNumberOfNewMessages();
                Connect();
                int n = nIndex + 1;

                if (n < newcount + 1)
                {
                    List <string> msglines = GetRawMessage(n);
                    string msgsubj = GetMessageSubject(msglines);

                    msg.Subject = msgsubj;
                    msg.From = new MailAddress(GetMessageFrom(msglines));
                    msg.Body = GetMessageBody(msglines);
                }

                Disconnect();
                return msg;
            }
            catch
            {
                return null;
            }
        }

        #endregion

        #region Private

        private bool Connect()
        {
            TcpClient sender = new TcpClient(POPServer, mPOPPort);
            byte[] outbytes;
            string input;

            try
            {
                ns = sender.GetStream();
                sr = new StreamReader(ns);

                sr.ReadLine();
                input = "user " + mPOPUserName + "\r\n";
                outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
                ns.Write(outbytes, 0, outbytes.Length);
                sr.ReadLine();

                input = "pass " + mPOPPass + "\r\n";
                outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
                ns.Write(outbytes, 0, outbytes.Length);
                sr.ReadLine();
                return true;

            }
            catch
            {
                return false;
            }
        }

        private void Disconnect()
        {
            string input = "quit" + "\r\n";
            Byte[] outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
            ns.Write(outbytes, 0, outbytes.Length);
            ns.Close();
        }

        private List <string> GetRawMessage(int messagenumber)
        {
            Byte[] outbytes;
            string input;
            string line = "";

            input = "retr " + messagenumber.ToString() + "\r\n";
            outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
            ns.Write(outbytes, 0, outbytes.Length);

            List <string> msglines = new List <string>();
            do
            {
                line = sr.ReadLine();
                msglines.Add(line);
            } while (line != ".");
            msglines.RemoveAt(msglines.Count - 1);

            return msglines;
        }

        private string GetMessageSubject(List <string> msglines)
        {
            string[] tokens;
            IEnumerator msgenum = msglines.GetEnumerator();
            while (msgenum.MoveNext())
            {
                string line = (string)msgenum.Current;
                if (line.StartsWith("Subject:"))
                {
                    tokens = line.Split(new Char[] { ' ' });
                    return tokens[1].Trim();
                }
            }
            return "None";
        }

        private string GetMessageFrom(List <string> msglines)
        {
            string[] tokens;
            IEnumerator msgenum = msglines.GetEnumerator();
            while (msgenum.MoveNext())
            {
                string line = (string)msgenum.Current;
                if (line.StartsWith("From:"))
                {
                    tokens = line.Split(new Char[] { ' <' });
                    return tokens[1].Trim(new Char[] { ' <', '>' });
                }
            }
            return "None";
        }

        private string GetMessageBody(List <string> msglines)
        {
            string body = "";
            string line = " ";
            IEnumerator msgenum = msglines.GetEnumerator();

            while (line.CompareTo("") != 0)
            {
                msgenum.MoveNext();
                line = (string)msgenum.Current;
            }

            while (msgenum.MoveNext())
            {
                body = body + (string)msgenum.Current + "\r\n";
            }
            return body;
        }

        private void DeleteMessage(int messagenumber)
        {
            Byte[] outbytes;
            string input;

            try
            {
                input = "dele " + messagenumber.ToString() + "\r\n";
                outbytes = System.Text.Encoding.ASCII.GetBytes(input.ToCharArray());
                ns.Write(outbytes, 0, outbytes.Length);
            }
            catch (Exception e)
            {
                return;
            }

        }

        #endregion

        #endregion
    }

    #endregion

方法二

一个asp.net 版本的邮件接收程序，我们知道，在asp+中发送Email是见很方便的事情,可是怎么进行收取pop信件的程序呢？看来只有拿出豆腐的杀手剑了：）
首先我们来看看这个程序的代码：
pop.aspx

<%@ Assembly Name="System.Net" %>
<%@ Import Namespace="System.Net" %>
<% @Import Namespace="System.Net.Sockets" %>
<%@ Import Namespace="System.IO" %>
<script language="C#" runat=server>
protected void Page_Load(Object Src, EventArgs E){
   String user="doufu";       //邮箱用户代码
   String pass="asp888.net";  //邮箱用户密码
   String popserver="localhost"; //pop服务器IP地址
   TCPClient tcpc = new TCPClient();
   if (0 == tcpc.Connect(popserver, 110))
   {
      //如果程序执行到这里，就表示连接Pop Server 成功
      Stream s;
      StreamReader sr ;
      String strCmd;
      Byte[] arrCmd;
      String strRet;
      String[] arrRet;    

      sr = new StreamReader(tcpc.GetStream(), Encoding.Default);
      Response.Write(sr.ReadLine() + "<br>");  //mail server 的欢迎语
      
      strRet=Logon(tcpc,user,pass);
      
      if(JudgeString(strRet)!="+OK"){
        Response.Write("对不起，没有这个用户/密码 不匹配");
        return;
      }

      //用户和密码 匹配，下面开始 统计用户信箱的信息
      //这个数组中包括了所有的返回信息
      arrRet=StaticMailBox(tcpc);
      if(arrRet[0]!="+OK"){
        Response.Write("出错了！");
        return;
      }
      Response.Write("当前的用户<font color=blue>" + user + "</font>的信箱中共有<font color=red>" + arrRet[1] + "</font>封,共占<font color=red>" + arrRet[2] + "</font>Byte");
      
      //收信
      arrRet=PopMail(tcpc,4);
      //判断返回
      if(arrRet[0]!="+OK"){
        Response.Write("出错了");
      }
      Response.Write("邮件日期：" + arrRet[1] + "\n<br>");
      Response.Write("发信人：" + arrRet[2] + "\n<br>");
      Response.Write("收信人：" + arrRet[3] + "\n<br>");
      Response.Write("邮件主题：" + arrRet[4] + "\n<br>");
      Response.Write("邮件内容：" + arrRet[5] + "\n<br>");
      //关闭Socket联结
      tcpc.Close();
    }
   else
    {
      Response.Write("Could not connect to server!");
    }
}
String SendPopCmd(TCPClient tcpc,String strCmd){
      Byte[] arrCmd;
      String strRet;
      StreamReader sr;
      Stream s;
      s=tcpc.GetStream();
      strCmd = strCmd + "\r\n";
      arrCmd= Encoding.Default.GetBytes(strCmd.ToCharArray());
      s=tcpc.GetStream();
      s.Write(arrCmd, 0, strCmd.Length);
      sr = new StreamReader(tcpc.GetStream(), Encoding.Default);
      strRet=sr.ReadLine();
      return strRet;
}
String Logon(TCPClient tcpc,String user,String pass){
      //这个函数的功能是 对 获得联结的用户 身份进行验证
      //发送 用户代码      
      String strRet;
      strRet=SendPopCmd(tcpc,"user " + user);
      strRet=SendPopCmd(tcpc,"pass " + pass);
      return strRet;
}
String[] StaticMailBox(TCPClient tcpc){
   String strRet;
   strRet=SendPopCmd(tcpc,"stat");
   if(JudgeString(strRet)!="+OK"){
     return "-ERR -ERR".Split(" ".ToCharArray());
   }
   String[] arrRet=strRet.Split(" ".ToCharArray());
   return arrRet;
}
String JudgeString(String strCheck){
   if(strCheck.Substring(0,3)!="+OK"){
     return "-ERR";
   }
   else
     return "+OK";
}
String[] PopMail(TCPClient tcpc,int i){
   String strRet;
   bool strBody=false;
   String[] arrRet =new String[10];
   String[] arrTemp;
   strRet=SendPopCmd(tcpc,"retr " + i.ToString());
   if(JudgeString(strRet)!="+OK"){
     //表示没有这个信件 或者 其他的错误
     return "-ERR -ERR".Split(" ".ToCharArray());
   }
   StreamReader sr;
   sr = new StreamReader(tcpc.GetStream(), Encoding.Default);
   Response.Write("\n<BR>");
   Response.Write("<font color=red>\n<BR>");
   while (sr.Peek()!=46)
   {
     //呵呵，不知道 为什么 非要是 46 才可以！
     strRet=sr.ReadLine();
     arrTemp=strRet.Split(":".ToCharArray());
     if(strRet=="")
        strBody=true; //现在开始接收 Body 的信息
     if(arrTemp[0]=="Date"){
          arrRet[1]=arrTemp[1];  //信件的发送日期
          }
     if(arrTemp[0]=="From")
        arrRet[2]=arrTemp[1];  //发信人
     if(arrTemp[0]=="To")
        arrRet[3]=arrTemp[1];  //收信人
     if(arrTemp[0]=="Subject")
        arrRet[4]=arrTemp[1];  //主题
     if(strBody){
        arrRet[5]=arrRet[5] + strRet + "\n";
     }
   }

   arrRet[0]="+OK";
   return arrRet;
}
</script>
好了大家通过这个程序，首先可以了解到pop(Post Ofice Protocal)协议，其次可以加深对asp.net的socket 程序的
理解，还可以通过这个程序接收ISP提供的没有Web方式收取邮件的程序对ISP的信箱进行管理。