QT c++ - QNetworkAccessManager帮助需要!类问题

我正试图从服务器下载一个页面到我的QT程序，但我一直在寻找方法来做到这一点，他们并没有真正工作很多。我不是QT/c++方面的专家，所以请谅解:)

好. .到目前为止，我使用了以下代码:

[旧代码]-检查更新的代码下面!

http.cpp

#include "http.h"
http::http(QObject *parent) :
    QObject(parent)
{
    qDebug() << "HTTP ST";
    http1 = new QHttp(this);
    connect(http1, SIGNAL(done(bool)), this, SLOT(httpdown())); // Correction 1.
    http1->setHost("localhost");
    http1->get("/test.php");
    qDebug() << "HTTP END";

}
void http::httpdown()
{
    qDebug() << "completed!";
    qDebug() << http1->readAll();

}

http.h

#ifndef HTTP_H
#define HTTP_H
#include <QtNetwork>
#include <QHttp>
#include <QDebug>
#include <QObject>
class http : public QObject
{
    Q_OBJECT
public:
    explicit http(QObject *parent = 0);
signals:
public slots:
    void httpdown();
private:
    QHttp *http1;
};
#endif // HTTP_H

问题是httpdown()永远不会被调用，我已经尝试了任何我知道的:(可能我没有正确地这样做。

帮助将非常感激。谢谢。

问题更新

我已经听到了alexisdm的建议，并检查QNetworkAccessManager。所以这里是在main()上正确工作的新代码。

当我从另一个类运行它时，我从来没有得到过信号。

http2.cpp

#include "http2.h"
http2::http2(QObject *parent) :
    QObject(parent)
{
    m_manager = new QNetworkAccessManager(this);
    connect(m_manager,SIGNAL(finished(QNetworkReply*)),this,SLOT(httpdown(QNetworkReply*)));
    QNetworkRequest request;
    request.setUrl(QUrl("http://localhost/test.php"));
    request.setRawHeader("User-Agent", "MyOwnBrowser 1.0");
    m_manager->get(request);
}
void http2::httpdown(QNetworkReply* result)
{
       QByteArray data= result->readAll();
       QString str(data);
       qDebug() <<  str;
}

http2.h

#ifndef HTTP2_H
#define HTTP2_H
#include <QObject>
#include <QDebug>
#include <QtNetwork>
#include <QNetworkReply>
class http2 : public QObject
{
    Q_OBJECT
public:
    explicit http2(QObject *parent = 0);
signals:
public slots:
    void httpdown(QNetworkReply* result);
private:
    QNetworkAccessManager* m_manager;
};
#endif // HTTP2_H

如果我直接在main。cpp下面调用它，像这样:

main.cpp

#include <QtCore/QCoreApplication>
#include "tcpserver.h"
#include "http2.h"
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    http2 h; // --> Working!!
    tcpserver mServer;
    return a.exec();
}

很好。但是，如果我在tcpserver类中像这样调用它:

tcpserver.cpp

#include "tcpserver.h"
#include "protocol.h"
#include "http2.h"
QTextStream in(stdin);
tcpserver::tcpserver(QObject *parent) :
    QObject(parent)
{
    server = new QTcpServer(this);
    [ ... Other Server Stuff ... ]
    // http2 h; // --> OLD CODE - Not Working :(
    http2 *h = new http2(this); // **--> NEW CODE working provided by alexisdm**
}

信号永远不会发生…怎么了?我是新来的!: P

无论如何，alexisdm说:"也许http对象在信号可以发出之前被销毁(例如，如果它被分配在堆栈上)"- 解决方案接受，下面的代码更正阅读此:QT c++ - QNetworkAccessManager需要帮助!课堂问题(链接到答案)

我该怎么做才能避免这种情况?

谢谢!div;)

http2 *h = new http2(this);

SIGNAL(bool)

SIGNAL(done(bool))