簡單郵件傳輸協定SMTP封裝類

作者：Asif Rasheed 翻譯：劉建強

在Internet上,Email是最流行的傳輸媒體。這篇文章包括兩個協定：. POP 3 協定： POP3協定（郵政傳輸協定）就是指從Email伺服器接收信件。我已經送出了一個封裝POP3協定的類。該協定官方的描述你可查閱RFC1225。 SMTP協定： SMTP (簡單郵件傳輸協定） 指發送郵件到它的目的地。 有關SMTP 協定的細節你可參考RCF 821 .我最新地貢獻是封裝了SMTP協定。我不能完全實作 SMTP協定但你可用它在許多應用場合發送郵件。該類有若幹方法，我選方法名同SMTP指令， 是以你很容易了解。 在該類中，我再一次使用了CSocket作為類成員,是以我能線上程中使用它. 下面是該類的編碼及注釋：

//

// 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;

}

// 發送"QUIT"指令到SMTP伺服器：

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;

}

// 發送"MAIL" 指令到SMTP伺服器：

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");

}

// 發送"DATA" 指令到 SMTP 伺服器：

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;

}

}

//本方法檢查伺服器的響應：

BOOL CSMTP::CheckResponse(int Type)

{

char buf [1000];

char temp[3];

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

buf[i]='/0';

// 從伺服器接收資料

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;

}

// 傳回錯誤消息

CString CSMTP::GetErrorMessage()

{

return m_ErrorMessage;

}

// 按照錯誤号準備錯誤資訊

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);

}　

這是該類一個小的實作：　

CSMTP m_smtp;

m_smtp.Connect("khi.compol.com","[email protected]");

m_smtp.Mail("[email protected]");

m_smtp.SetTo("[email protected]");

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

m_smtp.Disconnect();