怎样用c++实现后台发送邮件，100分

这个涉及到 c++网络编程 我把代码贴给你吧... 这个程序经过调试了 没有问题，可以发送邮件。

要创建工程两个主程序如下：
//*********************************SendMai.cpp
#include "StdAfx.h"
#include <stdlib.h>
#include "winsock2.h"
#include "base64.h"
#include <sys/stat.h>

#include <time.h>
#include <io.h>

//winsock 2.2 library
#pragma comment(lib,"ws2_32.lib")

#define SMTP_PORT 25 // Standard port for SMTP servers
#define RESPONSE_BUFFER_SIZE 1024
#define PARA_BUF 128
#define RESPONSE_NUM 6
#define _T(x) x

// Helper Code
struct response_code
{
UINT nResponse; // Response we're looking for
TCHAR* sMessage; // Error message if we don't get it
};

enum eResponse
{
GENERIC_SUCCESS = 0,
AUTHLOGIN_SUCCESS,
AUTH_SUCCESS,
CONNECT_SUCCESS,
DATA_SUCCESS,
QUIT_SUCCESS,
LAST_RESPONSE
};

TCHAR *response_buf;
static response_code response_table[RESPONSE_NUM]=
{
//GENERIC_SUCCESS
{250, _T("SMTP 服务器错误")},
//AUTHLOGIN_SUCCESS
{334, _T("SMTP 验证连接错误")},
//AUTH_SUCCESS
{235, _T("SMTP 用户名/密码验证错误")},
//CONNECT_SUCCESS
{220, _T("SMTP 服务器不可用")},
//DATA_SUCCESS
{354, _T("SMTP 服务器不能接收数据")},
//QUIT_SUCCESS
{221, _T("SMTP 没有中止会话")}

};

typedef struct _tagCONFIG_INFO {
char m_szServerName[PARA_BUF];
char m_nPort[1];
char m_nNeedAuth[1];
char m_szAccount[PARA_BUF];
char m_szPassword[PARA_BUF];
char m_szFrom[PARA_BUF];
char m_szTo[PARA_BUF];
char m_szUsername[PARA_BUF];
char m_szFilename[PARA_BUF*2];
char m_szSubject[PARA_BUF];
char m_szBody[1024];
}CONFIG_INFO, * LPCONFIG_INFO;

SOCKET sconnection;
CONFIG_INFO ci;

BOOL AuthorizationLogin();
BOOL GetResponse(UINT response_expected);
BOOL SendMail();

int main(int argc, char* argv[])
{
WSADATA wsock;
SOCKADDR_IN serAddr;
int nRet=0;
//初始化Winsock 2.2

printf("\nInitialising Winsock...\n");
if (WSAStartup(MAKEWORD(2,2),&wsock) != 0)
{
fprintf(stderr,"WSAStartup() failed %d\n, WSAGetLastError()");
exit(0);
}
printf("Initialised successfully.\n");

//创建监听socket
printf("\nCreating TCP Socket...\n");
if ((sconnection = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP))
== INVALID_SOCKET)
{
printf("Creation of socket failed %d\n", WSAGetLastError());
WSACleanup();
return 0;
}
printf("TCP Socket Created successfully.\n");

ZeroMemory(&ci,sizeof(CONFIG_INFO));
//邮件服务器
// printf("Enter mail server name: ");
// sprintf(ci.m_szServerName,"smtp.126.com");
// sprintf(ci.m_szServerName,"smtp.sohu.com");
// sprintf(ci.m_szServerName,"smtp.sina.com.cn");
printf("Please enter smtp Server Name:");
gets(ci.m_szServerName);
//设置SOCKADDR_IN地址结构
serAddr.sin_family = AF_INET;
serAddr.sin_port = htons(SMTP_PORT);
//From CAsyncSocket::Connect
serAddr.sin_addr.s_addr = inet_addr(ci.m_szServerName);
if (serAddr.sin_addr.s_addr == INADDR_NONE)
{
LPHOSTENT lphost;
lphost = gethostbyname(ci.m_szServerName);
if (lphost != NULL)
serAddr.sin_addr.s_addr = ((LPIN_ADDR)lphost->h_addr)->s_addr;
else
{
WSASetLastError(WSAEINVAL);
return 0;
}
}
//连接服务端
printf("Connecting to %s:%d...\n",
inet_ntoa(serAddr.sin_addr), htons(serAddr.sin_port));
if (connect(sconnection, (SOCKADDR *) &serAddr, sizeof(serAddr))
== SOCKET_ERROR)
{
printf("connection failed with error %d\n", WSAGetLastError());
closesocket(sconnection);
WSACleanup();
return 0;
}
printf("connection successfully.\n");

response_buf = new TCHAR[RESPONSE_BUFFER_SIZE];

if(!GetResponse(CONNECT_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//发送“EHLO %SMTP-Server Name%”：
char szHello[PARA_BUF];
sprintf(szHello,_T("EHLO %s\r\n"),ci.m_szServerName);
send(sconnection,szHello,strlen(szHello),0);
if(!GetResponse(GENERIC_SUCCESS))
{
printf("Cann't connect the server!\n");
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//用户名、密码
printf("Enter Account name: ");
gets(ci.m_szAccount);

printf("Enter passwd: ");
gets(ci.m_szPassword);

printf("Enter Sender Email: ");
gets(ci.m_szFrom);

printf("Enter Subject: ");
gets(ci.m_szSubject);

printf("Enter Receiver Email: ");
gets(ci.m_szTo);

printf("Enter Email Content: ");
gets(ci.m_szBody);

if(AuthorizationLogin())
{
if(SendMail())
printf("Send ok!\n");
}
printf("Closing the connection.\n");
closesocket(sconnection);
WSACleanup();
return 0;
}

//****************************************
// 函数功能：服务器验证
//****************************************
BOOL AuthorizationLogin()
{
char* szAccount;
char* szPassword;
printf("Authing......\n ");
//发送“AUTH LOGIN”：
send(sconnection,_T("AUTH LOGIN\r\n"), strlen(_T("AUTH LOGIN\r\n")),0);

if(!GetResponse(AUTHLOGIN_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//发送经过Base64编码的用户帐号：
base64_encode(ci.m_szAccount,strlen(ci.m_szAccount),&szAccount);
// char buf[200];
// base64_decode(szAccount,buf);
//注意添加回车换行
strcat(szAccount,"\r\n");
send(sconnection,szAccount,strlen(szAccount),0);

if(!GetResponse(AUTHLOGIN_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}
//发送经过Base64编码的用户密码
base64_encode(ci.m_szPassword,strlen(ci.m_szPassword),&szPassword);
strcat(szPassword,"\r\n");
send(sconnection,szPassword,strlen(szPassword),0);
if(!GetResponse(AUTH_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

return TRUE;
}

//****************************************
// 函数功能：获得服务器返回信息
//****************************************
BOOL GetResponse(UINT response_expected)
{
char szResponse[RESPONSE_BUFFER_SIZE];
UINT response;
response_code *pResp;

if(recv(sconnection,response_buf, RESPONSE_BUFFER_SIZE,0) == SOCKET_ERROR)
{
return FALSE;
}

strncpy(szResponse,response_buf,3);
sscanf(szResponse, _T("%d"), &response);

pResp = &response_table[response_expected];
if(response != pResp->nResponse)
{
printf(_T("%d:%s"), response, (LPCTSTR)pResp->sMessage);
return FALSE;
}

return TRUE;
}

//****************************************
// 函数功能：生成并传输邮件内容
//****************************************
BOOL SendMail()
{
char szFrom[PARA_BUF]={0},szTo[PARA_BUF]={0},szSubject[PARA_BUF]={0},szBodyHead[PARA_BUF*10]={0};
char szBody[PARA_BUF*20]={0},szContent[PARA_BUF*80]={0},szAttachment[PARA_BUF*10]={0},szTemp[PARA_BUF*50]={0};
char szDateTime[PARA_BUF]={0},szFileBuf[1024*5]={0};

printf("Sending Mail......\n ");
//发送Header中的“MAIL FROM”
sprintf(szFrom,_T("MAIL FROM:<%s>\r\n"),ci.m_szFrom);

send(sconnection,szFrom,strlen(szFrom),0);
if(!GetResponse(GENERIC_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//发送Header中的“RCPT TO”
sprintf(szTo,_T("RCPT TO:<%s>\r\n"),ci.m_szTo);
send(sconnection,szTo,strlen(szTo),0);

if(!GetResponse(GENERIC_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//发送“DATA\r\n”
send(sconnection,"DATA\r\n",strlen("DATA\r\n"),0);
if(!GetResponse(DATA_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}
//以下进行 Body 的处理
sprintf(szFrom,_T("FROM:%s<%s>\r\n"),ci.m_szUsername,ci.m_szFrom);
sprintf(szTo,_T("TO:<%s>\r\n"),ci.m_szTo);
time_t ltime=time(NULL);
_tzset();
sprintf(szDateTime,"Date:%s",ctime(<ime));

sprintf(szSubject,_T("Subject:%s\r\n"),ci.m_szSubject);

sprintf(szBodyHead,_T("X-Mailer: ntSmtp [ch]\r\n"));
strcat(szBodyHead,"MIME_Version:1.0\r\n");
strcat(szBodyHead,"Content-type:multipart/mixed;Boundary=ntSmtp\r\n\r\n");
strcat(szBodyHead,"--ntSmtp\r\n");
strcat(szBodyHead,"Content-type:text/plain;Charset=gb2312\r\n");
strcat(szBodyHead,"Content-Transfer-Encoding:8bit\r\n\r\n");

sprintf(szBody,_T("%s\r\n\r\n"),ci.m_szBody);

//以下进行附件的处理
if(!_access(ci.m_szFilename,0))
{
sprintf(szTemp,"--ntSmtp\r\n");
strcat(szTemp,"Content-Type:application/octet-stream;Name=%s\r\n");
strcat(szTemp,"Content-Disposition:attachment;FileName=%s\r\n");
strcat(szTemp,"Content-Transfer-Encoding:Base64\r\n\r\n");
strcat(szTemp,"%s\r\n\r\n");

sprintf(szContent,szFrom);
strcat(szContent,szTo);
strcat(szContent,szDateTime);
strcat(szContent,szSubject);
strcat(szContent,szBodyHead);
strcat(szContent,szBody);
HANDLE hFile;
hFile=CreateFile(ci.m_szFilename,GENERIC_READ,FILE_SHARE_READ, NULL
,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL);
if(hFile!=INVALID_HANDLE_VALUE)
{
struct _stat filestat;
_stat(ci.m_szFilename,&filestat);

DWORD dwNum;
ReadFile(hFile,szFileBuf,filestat.st_size,&dwNum,NULL);
char* file;
base64_encode(szFileBuf,strlen(szFileBuf),&file);
char fname[100]={0};
char ext[3]={0};
_splitpath(ci.m_szFilename,NULL,NULL,fname,ext);
strcat(fname,ext);
sprintf(szAttachment,szTemp,fname,fname,file);

CloseHandle(hFile);
strcat(szContent,szAttachment);
}
//连接成Content
strcat(szContent,"--ntSmtp\r\n.\r\n");
}
else
{
//连接成 Content
strcat(szContent,szFrom);
strcat(szContent,szTo);
strcat(szContent,szDateTime);
strcat(szContent,szSubject);
strcat(szContent,szBodyHead);
strcat(szContent,szBody);
strcat(szContent,"--ntSmtp\r\n.\r\n");
}

//发送 Content
send(sconnection,szContent,strlen(szContent),0);
if(!GetResponse(GENERIC_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

//发送Quit
send(sconnection,_T("QUIT\r\n"),strlen(_T("QUIT\r\n")),0);
if(!GetResponse(QUIT_SUCCESS))
{
closesocket(sconnection);
delete response_buf;
response_buf = NULL;
return FALSE;
}

return TRUE;
}本回答被提问者和网友采纳

我在linux上是通过调用curl实现的