POCO lib“未在此范围内声明MailMessage”

Question

我正在使用POCO lib发送电子邮件。它给了我这些错误：

(_UInt16 port = 587;_) UInt16 Was not declared in this scope
(_MailMessage message;_) MailMessage Was not declared in this scope

以下是我的代码的一部分：

#include <Poco/Net/MailMessage.h>
#include <Poco/Net/MailRecipient.h>
#include <Poco/Net/SMTPClientSession.h>
#include <Poco/Net/NetException.h>

MailMessage message;

QString host = "smtp.gmail.com";
UInt16 port = 587;
QString user = "xxxxxxxx";
QString password = "111111111AbCd";
QString to = "xxxxxxxxxxxx";
QString from = "xxxxxxxxxx";
QString subject = "xxxxxxxxxxxxxx";

subject = MailMessage::encodeWord(subject, "UTF-8");

修改

使用Poco::Net::MailMessage时，我收到以下错误： Click to see the image