转载转载转载转载转载转载转载转载转载Public Sub SENDEmail(MailServerName As String, FromName As String, FromEmailAddress As String, ToName As String, ToEmailAddress As String, EmailSubject As String, EmailBodyOfMessage As String)
Form2.Winsock1.LocalPort = 0 ' Must set local port to 0 (Zero) or you can only send 1 e-mail pre program start
If Form2.Winsock1.State = sckClosed Then ' Check to see if socet is closed DateNow = Format(Date, "Ddd") & ", " & Format(Date, "dd Mmm YYYY") & " " & Format(Time, "hh:mm:ss") & "" & " -0600" first = "mail from:" + Chr(32) + FromEmailAddress + vbCrLf ' Get who's sending E-Mail address Second = "rcpt to:" + Chr(32) + ToEmailAddress + vbCrLf ' Get who mail is going to Third = "Date:" + Chr(32) + DateNow + vbCrLf ' Date when being sent Fourth = "From:" + Chr(32) + FromName + vbCrLf ' Who's Sending Fifth = "To:" + Chr(32) + ToName + vbCrLf ' Who it going to Sixth = "Subject:" + Chr(32) + EmailSubject + vbCrLf ' Subject of E-Mail Seventh = EmailBodyOfMessage + vbCrLf ' E-mail message body Ninth = "mouse mailer" + vbCrLf ' What program sent the e-mail, customize this Eighth = Fourth + Third + Ninth + Fifth + Sixth ' Combine for proper SMTP sending Form2.Winsock1.Protocol = sckTCPProtocol ' Set protocol for sending Form2.Winsock1.RemoteHost = MailServerName ' Set the server address Form2.Winsock1.RemotePort = 25 ' Set the SMTP Port Form2.Winsock1.Connect ' Start connection
Form2.Winsock1.LocalPort = 0 ' Must set local port to 0 (Zero) or you can only send 1 e-mail pre program start
If Form2.Winsock1.State = sckClosed Then ' Check to see if socet is closed
DateNow = Format(Date, "Ddd") & ", " & Format(Date, "dd Mmm YYYY") & " " & Format(Time, "hh:mm:ss") & "" & " -0600"
first = "mail from:" + Chr(32) + FromEmailAddress + vbCrLf ' Get who's sending E-Mail address
Second = "rcpt to:" + Chr(32) + ToEmailAddress + vbCrLf ' Get who mail is going to
Third = "Date:" + Chr(32) + DateNow + vbCrLf ' Date when being sent
Fourth = "From:" + Chr(32) + FromName + vbCrLf ' Who's Sending
Fifth = "To:" + Chr(32) + ToName + vbCrLf ' Who it going to
Sixth = "Subject:" + Chr(32) + EmailSubject + vbCrLf ' Subject of E-Mail
Seventh = EmailBodyOfMessage + vbCrLf ' E-mail message body
Ninth = "mouse mailer" + vbCrLf ' What program sent the e-mail, customize this
Eighth = Fourth + Third + Ninth + Fifth + Sixth ' Combine for proper SMTP sending Form2.Winsock1.Protocol = sckTCPProtocol ' Set protocol for sending
Form2.Winsock1.RemoteHost = MailServerName ' Set the server address
Form2.Winsock1.RemotePort = 25 ' Set the SMTP Port
Form2.Winsock1.Connect ' Start connection
WaitFor ("220")
Form1.StatusTxt.Caption = "正在连接...."
Form1.StatusTxt.Refresh
Form2.Winsock1.SendData ("HELO worldcomputers.com" + vbCrLf) WaitFor ("250") Form1.StatusTxt.Caption = "连接成功"
Form1.StatusTxt.Refresh Form2.Winsock1.SendData (first) Form1.StatusTxt.Caption = "正在发送邮件...."
Form1.StatusTxt.Refresh WaitFor ("250") Form2.Winsock1.SendData (Second) WaitFor ("250") Form2.Winsock1.SendData ("data" + vbCrLf)
WaitFor ("354")
Form2.Winsock1.SendData (Eighth + vbCrLf)
Form2.Winsock1.SendData (Seventh + vbCrLf)
Form2.Winsock1.SendData ("." + vbCrLf) WaitFor ("250") Form2.Winsock1.SendData ("quit" + vbCrLf)
'Form1.StatusTxt.Caption = "Disconnecting"
Form1.StatusTxt.Refresh WaitFor ("221") Form2.Winsock1.Close
Else
MsgBox (Str(Form2.Winsock1.State))
End If
End Sub
服务器
2.SMTP是个请求/响应协议，命令和响应都是基于ASCII文本，并以CR和LF符结束。响应包括一个表示返
回状态的三位数字代码
3.SMTP在TCP协议25号端口监听连接请求
4.连接和发送过程：a.建立TCP连接
b.客户端发送HELO命令以标识发件人自己的身份，然后客户端发送MAIL命令
服务器端正希望以OK作为响应，表明准备接收
c.客户端发送RCPT命令，以标识该电子邮件的计划接收人，可以有多个RCPT行
服务器端则表示是否愿意为收件人接受邮件
d.协商结束，发送邮件，用命令DATA发送
e. 以.表示结束输入内容一起发送出去
f.结束此次发送，用QUIT命令退出。
5.另外两个命令：
VRFY---用于验证给定的用户邮箱是否存在，以及接收关于该用户的详细信息。
EXPN---用于扩充邮件列表。6.邮件路由过程：
SMTP服务器基于‘域名服务DNS中计划收件人的域名来路由电子邮件。SMTP服务器基于DNS中的MX记录
来路由电子邮件，MX记录注册了域名和相关的SMTP中继主机，属于该域的电子邮件都应向该主机发送。若SMTP服务器mail.abc.com收到一封信要发到[email protected]:a.Sendmail请求DNS给出主机sh.abc.com的CNAME记录，如有，假若CNAME到shmail.abc.com，则再次
请求shmail.abc.com的CNAME记录，直到没有为止
b.假定被CNAME到shmail.abc.com,然后sendmail请求@abc.com域的DNS给出shmail.abc.com的MX记录，
shmail MX 5 shmail.abc.com
10 shmail2.abc.com
c. Sendmail最后请求DNS给出shmail.abc.com的A记录，即IP地址，若返回值为1.2.3.4
d. Sendmail与1.2.3.4连接，传送这封给[email protected]的信到1.2.3.4这台服务器的SMTP后台程序7.SMTP基本命令集：命令 描述
------------------------------
HELO 向服务器标识用户身份
发送者能欺骗，说谎，但一般情况下服务器都能检测到。MAIL 初始化邮件传输
mail from:
RCPT 标识单个的邮件接收人；常在MAIL命令后面
可有多个rcpt to:
DATA 在单个或多个RCPT命令后，表示所有的邮件接收人已标识，并初始化数据传输，以.结束。
VRFY 用于验证指定的用户/邮箱是否存在；由于安全方面的原因，服务器常禁止此命令
EXPN 验证给定的邮箱列表是否存在，扩充邮箱列表，也常被禁用
HELP 查询服务器支持什么命令
NOOP 无操作，服务器应响应OK
QUIT 结束会话
RSET 重置会话，当前传输被取消
--------------------------------8. MAIL FROM命令中指定的地址是称作 envelope from地址，不需要和发送者自己的地址是一致的。
RCPT TO 与之等同，指明的接收者地址称为envelope to地址，而与实际的to：行是什么无关。
9.为什么没有RCPT CC和RCPT BCC:?
所有的接收者协商都通过RCPT TO命令来实现，如果是BCC，则协商发送后在对方接收时被删掉信封接收者
10.邮件被分为信封部分，信头部分和信体部分
envelope from, envelope to 与message from:, message to:完全不相干。
evnelope是由服务器主机间SMTP后台提供的，而message from/to是由用户提供的。有无冒号也是区别。11. 怎样由信封部分检查是否一封信是否是伪造的？
a. received行的关联性。
现在的SMTP邮件传输系统，在信封部分除了两端的内部主机处理的之个，考虑两个公司防火墙之间
的部分，若两台防火墙机器分别为Ａ和Ｂ，但接收者检查信封received：行时发现经过了C.则是伪造的。
b. received：行中的主机和IP地址对是否对应如：
Receibed: from galangal.org (turmeric.com [104.128.23.115] by mail .bieberdorf.edu....
c. 被人手动添加在最后面的received行：
Received: from galangal.org ([104.128.23.115]) by mail .bieberdorf.edu (8.8.5)
Received: from lemongrass.org by galangal.org (8.7.3)
Received: from graprao.com by lemongrass.org (8.6.4)转载