QT 如何实现HTTP的同步访问

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#include <QtCore/QCoreApplication>
#include <QObject>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QUrlQuery>
#include <QUrl>
#include <QEventLoop>
#include <QTextCodec>
#include <QTimer>


void httpGET(const QString& strUrl, QString& response, int& statusCode)
{
	assert(!strUrl.isEmpty());
	const QUrl url = QUrl::fromUserInput(strUrl);
	assert(url.isValid());

	//
	QNetworkAccessManager* manager = new QNetworkAccessManager;
	QNetworkRequest request(url);
	request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
	QScopedPointer<QNetworkReply> reply(manager->get(request));
	
	//wait.
	QEventLoop eventLoop;
	QTimer::singleShot(5000, &eventLoop, [&]() { if (eventLoop.isRunning()) { eventLoop.quit(); } });
	QObject::connect(reply.data(), &QNetworkReply::finished, &eventLoop, &QEventLoop::quit);
	eventLoop.exec(QEventLoop::ExcludeUserInputEvents);

	//status code
	statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
	//response
	if (reply->error() == QNetworkReply::NoError)
	{
		QByteArray data = reply->readAll();
		response = QString::fromLocal8Bit(data);
	}
	else 
	{
		response = reply->errorString().toUtf8();
	}
	reply->deleteLater();
}

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

	int statusCode = 0;
	QString response;
	QString strUrl = "http://wthrcdn.etouch.cn/weather_mini?citykey=101010100";
	httpGET(strUrl, response, statusCode);

	qDebug() << "statusCode=" << statusCode << "nresponse=" << response;

    return a.exec();
}