C++实现含附件的邮件发送功能

//
#include "Csmtp.h"
#pragma comment(lib, "Kernel32.lib") 

int main()
{ 

 Csmtp mail(
  25,
  "smtp.126.com",
  "username@126.com",// 来源邮箱
  "pwd",
  "username@126.com" //目标邮箱
  );

 if (!mail.CReateSocket())
 {
  cout << "ReateSocket failed!" << endl;
  return -1;//
 }
 mail.setTitle("test mail");
 mail.setContent("this is content.");

 mail.addfile("test1.png"); //添加附件
 mail.addfile("test2.png"); //添加附件

 mail.SendMail(); //类主函数

 return 0; 
} 

#include  
#include  
#include 
#include  

#include  //适用平台 Windows

#pragma comment(lib, "ws2_32.lib") /*链接ws2_32.lib动态链接库*/ 
 // POP3服务器（端口：110） Csmtp服务器（端口：25） 
using namespace std;
class Csmtp 
{ 

 int port; 
 string domain; 
 string user; 
 string pass; 
 string target; 
 string title; //邮件标题
 string content; //邮件内容


 HOSTENT* pHostent;
 SOCKET sockClient; //客户端的套接字
 vector  filename; //存储附件名的向量

public: 

 Csmtp( 
  int _port, //端口25
  string _domain,  //域名
  string _user,  //发送者的邮箱
  string _pass,  //密码
  string _target)  //目标邮箱
 :port(_port),domain(_domain),user(_user),pass(_pass), target(_target){};//内容 
 bool CReateSocket();
 void setTitle(string tem){title = tem;}
 void setContent(string tem){content = tem;}

 int SendAttachment(SOCKET &sockClient);
 int SendMail();
 void addfile(string str){filename.push_back(str);}

}; 

#include "Csmtp.h"
//#include //异常类
static const char base64Char[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 
char* base64Encode(char const* origSigned, unsigned origLength) 
{ 
 unsigned char const* orig = (unsigned char const*)origSigned; // in case any input bytes have the MSB set 
 if (orig == NULL) return NULL; 

 unsigned const numOrig24BitValues = origLength / 3; 
 bool havePadding = origLength > numOrig24BitValues * 3; 
 bool havePadding2 = origLength == numOrig24BitValues * 3 + 2; 
 unsigned const numResultBytes = 4 * (numOrig24BitValues + havePadding); 
 char* result = new char[numResultBytes + 3]; // allow for trailing '/0' 

 // Map each full group of 3 input bytes into 4 output base-64 characters: 
 unsigned i; 
 for (i = 0; i < numOrig24BitValues; ++i) 
 { 
  result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F]; 
  result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F]; 
  result[4 * i + 2] = base64Char[((orig[3 * i + 1] << 2) | (orig[3 * i + 2] >> 6)) & 0x3F]; 
  result[4 * i + 3] = base64Char[orig[3 * i + 2] & 0x3F]; 
 } 

 // Now, take padding into account. (Note: i == numOrig24BitValues) 
 if (havePadding) 
 { 
  result[4 * i + 0] = base64Char[(orig[3 * i] >> 2) & 0x3F]; 
  if (havePadding2) 
  { 
   result[4 * i + 1] = base64Char[(((orig[3 * i] & 0x3) << 4) | (orig[3 * i + 1] >> 4)) & 0x3F]; 
   result[4 * i + 2] = base64Char[(orig[3 * i + 1] << 2) & 0x3F]; 
  } 
  else 
  { 
   result[4 * i + 1] = base64Char[((orig[3 * i] & 0x3) << 4) & 0x3F]; 
   result[4 * i + 2] = '='; 
  } 
  result[4 * i + 3] = '='; 
 } 

 result[numResultBytes] = '\0'; 
 return result; 
} 


int Csmtp::SendAttachment(SOCKET &sockClient) /*发送附件*/ 
{ 
 for (std::vector::iterator iter = filename.begin();iter != filename.end(); iter++) 
 { 
  cout << "Attachment is sending··· " << endl; 

  string path=*iter;
  ifstream ifs(path, ios::in | ios::binary); //'或链接2个属性，以输入、二进制打开'
  if (false == ifs.is_open()) 
  { 
   cout<<"无法打开文件！"<h_addr_list[i]!=NULL;i++) 
  {
   string tem = inet_ntoa(*(struct in_addr *)pHost->h_addr_list[i]);
   ip_list += tem;
   ip_list += "\n";
  } 
 } 
 else 
 { 
  cout<<"获取主机信息失败..."<h_addr_list[0]); //得到smtp服务器的网络字节序的ip地址  



 addrServer.sin_family = AF_INET; 
 addrServer.sin_port = htons(port); //连接端口25 
 //int connect (SOCKET s , const struct sockaddr FAR *name , int namelen );
 err = connect(sockClient, (SOCKADDR*)&addrServer, sizeof(SOCKADDR)); //向服务器发送请求 
 cout<<"connect:"<\r\nrcpt to:<"+target+">\r\n";
 send(sockClient, message.c_str(), message.length(), 0); 
 buff[recv(sockClient, buff, 500, 0)]='\0';
 //cout<<"mail from: "<