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zhengjb:
我晕,BitmapBytes类没找到!
Flex 图片压缩、上传 -
aniyo:
恩,学习了,原来只知道like只能用$$钱钱这个,不知道还可以 ...
ibatis sqlMap.xml 文件 like 查询的三种方案 -
slang88:
很好用。拿走了、谢谢LZ
Flex 饼形图 piechart 柱形图 columnchart 条形图 barchart 折线图 linechart -
liuyuan0371:
...
Flex 上传图片 预览 加载图片到内存 -
huangtaodada:
就要 这功能
Flex 饼形图 piechart 柱形图 columnchart 条形图 barchart 折线图 linechart
using System; using System.Text; using System.IO; using System.Net; using System.Net.Sockets; using System.Collections; namespace SkyDev.Web.Mail { 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="GB2312"; } /// <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 } using System; using NUnit.Framework; namespace SkyDev.Web.Mail { /// <summary> /// Test 的摘要说明。 /// </summary> [TestFixture] public class TestSmtpMail { //安装测试用例,完成初始化操作 [SetUp] public void SetUp() { } //测试结束完成清理操作 [TearDown] public void TearDown() { } [Test] public void TestMailAttachments() { SkyDev.Web.Mail.MailAttachments attachments=new MailAttachments(); Assert.AreEqual(0,attachments.Count,"初始化MailAttachments"); attachments.Add("c:\\autoexec.bat"); Assert.AreEqual(1,attachments.Count,"增加附件(附件确实存在)"); attachments.Add("c:\\autoexec.dat.txt"); Assert.AreEqual(1,attachments.Count,"增加附件(附件不存在)"); attachments.Clear(); Assert.AreEqual(0,attachments.Count,"清除附件"); } [Test] public void TestMailMessage() { MailMessage message=new MailMessage(); Assert.AreEqual(0,message.Attachments.Count,"初始化MailAttachments"); Assert.AreEqual(MailFormat.Text,message.BodyFormat,"邮件格式"); Assert.AreEqual("GB2312",message.Charset,"缺省的字符集"); } [Test] public void TestSendMail() { SmtpMail.SmtpServer="smtp.126.com"; MailMessage mail=new MailMessage(); mail.From="qs1976@126.com"; mail.FromName="曾青松"; mail.AddRecipients("qs1976@126.com"); mail.Subject="主题:测试邮件"; mail.BodyFormat=MailFormat.Text; mail.Body="测试的内容."; mail.Attachments.Add("c:\\test.txt"); SmtpMail.Send(mail,"","");//请填写自己的测试邮件帐号 } } }
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本文将深入探讨如何使用C#实现应用程序发送邮件以及同步TCP接收邮件的功能,这涉及到网络通信中的SMTP(Simple Mail Transfer Protocol)和POP3(Post Office Protocol version 3)协议。 首先,让我们来理解SMTP...
1. 连接:程序首先需要与SMTP服务器建立TCP连接。在C#或C代码中,这通常通过Socket类实现,设置好服务器地址和端口号后,进行连接操作。 2. 身份验证:连接建立后,客户端需要向服务器提供用户名和密码进行身份验证...
在C#中,这通常通过`System.Net.Mail`命名空间的`SmtpClient`类来实现,它可以设置SMTP服务器地址、端口、身份验证方式等参数,然后使用`Send`方法发送邮件。 2. **POP3/IMAP服务器**:POP3和IMAP服务器允许用户从...
本文将深入探讨C#语言中实现TCP/IP通信的相关知识点,通过提供的"TCP/IP通信c#例程",我们将了解如何创建服务器端和客户端,以及如何进行数据的发送和接收。 首先,TCP/IP协议栈由四层组成:应用层、传输层、网络层...
在C#中实现这些功能,可以使用SmtpClient类来处理SMTP通信,MailMessage类来构建邮件,以及Pop3Client类来处理POP3通信。下面是一个基本的示例: ```csharp using System.Net; using System.Net.Mail; // 创建邮件...
C#中的System.Net.Sockets命名空间提供了TcpClient和TcpListener类,用于实现TCP通信。TcpClient类用于客户端,它负责发起连接请求并发送接收数据;而TcpListener类用于服务端,监听指定端口的连接请求,并在接收到...
在发送电子邮件时,SMTP客户端与SMTP服务器建立TCP连接,然后按照SMTP命令交互,完成邮件的发送。 2. **编程语言实现SMTP Email** - **Python**: Python中的`smtplib`库提供了方便的SMTP接口。例如,你可以创建一...
通过阅读和分析源码,你可以了解到如何使用编程语言(如Python、Java、C#等)实现SMTP通信,包括如何构造SMTP命令、处理服务器响应以及封装邮件内容。 此外,源码可能还涉及以下知识点: - **邮件格式**:邮件通常...
SMTP服务器通常在TCP的25端口监听。要收发邮件,用户需要一个支持POP3服务的邮箱,因为POP3允许客户端离线下载邮件,它在TCP的110端口工作。 6.1.2 **SMTP基本命令** SMTP允许用户通过验证(如ESMTP)发送邮件。...