简单邮件传输协议SMTP封装类



作者:Asif Rasheed 翻译:刘建强


在Internet上,Email是最流行的传输媒体。这篇文章包括两个协议:. POP 3 协议: POP3协议(邮政传输协议)就是指从Email服务器接收信件。我已经提交了一个封装POP3协议的类。该协议官方的描述你可查阅RFC1225。 SMTP协议: SMTP (简单邮件传输协议) 指发送邮件到它的目的地。 有关SMTP 协议的细节你可参考RCF 821 .我最新地贡献是封装了SMTP协议。我不能完全实现 SMTP协议但你可用它在许多应用场合发送邮件。该类有若干方法,我选方法名同SMTP命令, 所以你很容易理解。 在该类中,我再一次使用了CSocket作为类成员,所以我能在线程中使用它. 下面是该类的编码及注释:


//////////////////////////////////////////////////////////////////////

// SMTP.h: interface for the CSMTP class.

//

//////////////////////////////////////////////////////////////////////


#if !defined(AFX_SMTP_H__617F7E82_7F4D_11D1_88A0_00001C302581__INCLUDED_)

#define AFX_SMTP_H__617F7E82_7F4D_11D1_88A0_00001C302581__INCLUDED_


#if _MSC_VER >= 1000

#pragma once

#endif // _MSC_VER >= 1000


#define CONNECTION_CHECK 0

#define HELLO_CHECK 1

#define MAIL_CHECK 2

#define RCPT_CHECK 3

#define DATA_START_CHECK 4

#define DATA_END_CHECK 5

#define QUIT_CHECK 6

#define DATA_CHECK 7



class CSMTP

{

public:

BOOL Mail(); //

CString GetErrorMessage();

BOOL Data(CString Subject, CString Body);

CString GetTo();

BOOL SetTo(CString to);

CString GetFrom();

void SetFrom(CString from);

BOOL Mail(CString from);

BOOL Disconnect();

CString GetHost();

void SetHost(CString Host);

BOOL Connect(CString Host, CString Me);

BOOL Connect();

CSMTP();

virtual ~CSMTP();


private:

CString GetError(CString Response);

CString m_ErrorMessage;

BOOL CheckResponse(int Type);

int m_NoOfTo;

CStringArray m_To;

CString m_From;

CSocket m_SMTPServer;

CString m_Host;

};


#endif // !defined(AFX_SMTP_H__617F7E82_7F4D_11D1_88A0_00001C302581__INCLUDED_)



//////////////////////////////////////////////////////////////////////////

// SMTP.cpp: implementation of the CSMTP class.

//

//////////////////////////////////////////////////////////////////////


#include "stdafx.h"

#include "MailSend.h"

#include "SMTP.h"


#ifdef _DEBUG

#undef THIS_FILE

static char THIS_FILE[]=__FILE__;

#define new DEBUG_NEW

#endif


//////////////////////////////////////////////////////////////////////

// Construction/Destruction

//////////////////////////////////////////////////////////////////////


CSMTP::CSMTP()

{

m_NoOfTo = 0;

m_SMTPServer.Create();

}


CSMTP::~CSMTP()

{

m_SMTPServer.Close();

}


// Connect to the SMTP Server

BOOL CSMTP::Connect()

{

return Connect(m_Host,m_From);

}


// Connect to the SMTP Server

BOOL CSMTP::Connect(CString Host,CString From)

{

if (!m_SMTPServer.Connect(Host,25)) // 25 for SMTP Port

{

m_ErrorMessage = _T("Server cannot be connected");

return FALSE;

}

else

{

if(CheckResponse(CONNECTION_CHECK)==FALSE)

return FALSE;


char buf [512];


wsprintf (buf, "HELO %s\r\n", (LPCSTR) From);

m_SMTPServer.Send(buf, strlen (buf));

if (CheckResponse(HELLO_CHECK)==FALSE)

return FALSE;

else

return TRUE;


return TRUE;

}

}


// Setting the Host String

void CSMTP::SetHost(CString Host)

{

m_Host = Host;

}


// Returing the Host String

CString CSMTP::GetHost()

{

return m_Host;

}


// 发送"QUIT"命令到SMTP服务器:

BOOL CSMTP::Disconnect()

{

char buf[256];


wsprintf (buf, "QUIT \r\n");

m_SMTPServer.Send(buf, strlen (buf));

if (CheckResponse(QUIT_CHECK)==FALSE)

return FALSE;

else

return TRUE;

}


// 发送"MAIL" 命令到SMTP服务器:

BOOL CSMTP::Mail(CString from)

{

char buf[256];


wsprintf (buf, "MAIL From:<%s>\r\n", (LPCSTR) from);

m_SMTPServer.Send(buf, strlen (buf));

if (CheckResponse(MAIL_CHECK)==FALSE)

return FALSE;

else

return TRUE;

}


// Setting the From string

void CSMTP::SetFrom(CString from)

{

m_From = from;

}


// Returing the From string

CString CSMTP::GetFrom()

{

return m_From;

}


// Setting the TO string

BOOL CSMTP::SetTo(CString to)

{

char buf[256];

m_To.Add(to); // Saving vale of to


wsprintf (buf, "RCPT TO:<%s>\r\n", (LPCSTR) to);

m_SMTPServer.Send(buf, strlen (buf));

if (CheckResponse(RCPT_CHECK)==FALSE)

return FALSE;

else

return TRUE;


}


// Returing the TO string

CString CSMTP::GetTo()

{

if(m_To.GetSize()>=m_NoOfTo)

{

m_NoOfTo++;

return m_To[m_NoOfTo-1];

}

else

return _T("No more To available");

}


// 发送"DATA" 命令到 SMTP 服务器:

BOOL CSMTP::Data(CString Subject, CString Body)

{

char buf[256];


wsprintf (buf, "DATA\r\n");


m_SMTPServer.Send(buf, strlen (buf));

if (CheckResponse(DATA_CHECK)==FALSE)

return FALSE;

else

{

wsprintf (buf, "SUBJECT:%s\r\n", (LPCSTR) Subject);

m_SMTPServer.Send(buf, strlen (buf));


wsprintf (buf, "%s\r\n", (LPCSTR) Body);

m_SMTPServer.Send(buf, strlen (buf));


wsprintf (buf, ".\r\n");

m_SMTPServer.Send(buf, strlen (buf));


return TRUE;

}

}


//本方法检查服务器的响应:

BOOL CSMTP::CheckResponse(int Type)

{

char buf [1000];

char temp[3];


for (int i=0;i < 512;i++)

buf[i]='\0';


//从服务器接收数据

m_SMTPServer.Receive(buf, sizeof(buf));

strncpy(temp,buf,3);

int temp2 = atoi(temp);

switch (Type)

{

case CONNECTION_CHECK:

if (temp2 != 220)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;


case HELLO_CHECK:

if (temp2 != 250)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case MAIL_CHECK:

if (temp2 != 250)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case RCPT_CHECK:

if (temp2 != 250)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case DATA_START_CHECK:

if (temp2 != 354)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case DATA_END_CHECK:

if (temp2 != 250)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case QUIT_CHECK:

if (temp2 != 221)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;

case DATA_CHECK:

if (temp2 != 354)

{

m_ErrorMessage = GetError((LPCTSTR)buf);

return FALSE;

}

break;


}

return TRUE;

}


// 返回错误消息

CString CSMTP::GetErrorMessage()

{

return m_ErrorMessage;

}


// 按照错误号准备错误信息

CString CSMTP::GetError(CString Response)

{

if(Response.Find("211"))

return _T("System status or system help reply");

if(Response.Find("214"))

return _T("Help Message");

if(Response.Find("220"))

return _T("Service is ready");

if(Response.Find("221"))

return _T("Service closing transmission channel");

if(Response.Find("250"))

return _T("Requested mail action okay, completed");

if(Response.Find("251"))

return _T("user not local: will forward to forward path");

if(Response.Find("354"))

return _T("Start mail input; end with

.

");


return _T("No Error Number is matched with ")+Response;

}


// Just overloading of the Mail method

BOOL CSMTP::Mail()

{

return Mail(m_From);

} 

这是该类一个小的实现: 


CSMTP m_smtp;

m_smtp.Connect("khi.compol.com","aasif@khi.compol.com");

m_smtp.Mail("aasif@khi.compol.com");

m_smtp.SetTo("zafir@home.com");

m_smtp.Data("test message","This is a test message ... ");

m_smtp.Disconnect();