c++ - 使用 SMTP 协议(protocol)和 boost 库发送电子邮件

Question

我正在尝试使用 SMTP 协议(protocol)和 boost 库发送电子邮件但出于某种原因，我无法连接到 hotmail smtp 服务器并向自己发送电子邮件。

这是我的代码:我做错了什么？

    DNS_RECORD* ppQueryResultsSet = NULL;

    // dns mx lookup
    DnsQuery(L"hotmail.com", DNS_TYPE_MX, DNS_QUERY_STANDARD, NULL, &ppQueryResultsSet, NULL);

    if (ppQueryResultsSet == NULL)
        return false;

    // i am getting the mx servers (i.e: mx3.hotmail.com)
    wcout << "MX Host name: " << ppQueryResultsSet->Data.MX.pNameExchange << endl;
    DnsRecordListFree(ppQueryResultsSet, DnsFreeRecordList);

    string host_name = String_Convertion::WStringToString(ppQueryResultsSet->Data.MX.pNameExchange);

    // setting up socket connection
    boost::asio::io_service io_service;
    tcp::resolver resolver(io_service);
    tcp::resolver::query query(host_name, "25");
    tcp::resolver::iterator endpoint_iterator = resolver.resolve(query), end;
    tcp::socket socket(io_service);

    // connecting to the server
    boost::system::error_code error_code_connect;
    boost::asio::connect(socket, endpoint_iterator, end, error_code_connect);
    if (error_code_connect)
    {
        cout << "Error connecting to SMTP Server" << endl;
        return false;
    }

    boost::system::error_code error;
    std::string temp_buf;
    boost::array<char, 128> buf;
    size_t len;

    // settings the packets to send
    list<string> packets;
    packets.push_back("HELO");
    packets.push_back("MAIL FROM: xxx@xxx.xxx");
    packets.push_back("VRFY xxx@xxx.xxx");
    packets.push_back("RCPT TO: x@hotmail.com"); 
    packets.push_back("DATA");
    packets.push_back("Subject: subject!");
    packets.push_back("hi how are you doing?.");
    packets.push_back("QUIT");
    list<string>::iterator it;
    // iterating to send the packets
    for (it = packets.begin(); it != packets.end(); it++)
    {
        socket.write_some(boost::asio::buffer(*it+"\r\n"));
        len = socket.read_some(boost::asio::buffer(buf), error);
        temp_buf = buf.data();
        temp_buf = temp_buf.substr(0, len);
        cout << temp_buf << endl;
    }

Answer 1

我认为您需要了解一下 boost:asio 的工作原理。本质上，您正在创建一个服务，但从不调用 run()。看聊天样本here ，并注意它生成一个专门用于执行工作的线程:

boost::thread t(boost::bind(&boost::asio::io_service::run, &io_service));