// client.h    class Client : public QObject {        Q_OBJECT    public:        explicit Client(const QString &url);        void sendData(const QString &data);    public slots:        void replyFinished(QNetworkReply* reply);    private:        void waitForFinish(const QHttp  &http);        QNetworkAccessManager* m_manager;        QString mUrl;};// client.cpp#include <QNetworkAccessManager>#include <QNetworkReply>#include <QUrl>Client::Client(const QString &url) {    mUrl = url;    m_manager = new QNetworkAccessManager(this);    connect(m_manager, SIGNAL(finished(QNetworkReply*)), this,            SLOT(replyFinished(QNetworkReply*)));}void Client::replyFinished(QNetworkReply* reply) { // 应答槽函数    if (reply && reply->error() == QNetworkReply::NoError) {        QByteArray data = reply->readAll();        qDebug() << "---------------------------------\n" <<  data;    } else {        // error    }    reply->close();}void Client::sendData(const QString &data) { // data为发送的数据    QNetworkRequest request;    request.setUrl(QUrl(mUrl)); // 设置url    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded"); // 设置头信息    m_manager->post(request, data.toUtf8());}

QString Client::sendData(const QString &data) {    m_manager = new QNetworkAccessManager(this);    QNetworkRequest request;    QEventLoop loop; // 使用QEventLoop实现阻塞    QNetworkReply *reply;    request.setUrl(QUrl(mUrl));    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");    reply = m_manager->post(request, data.toUtf8());    connect(m_manager, SIGNAL(finished(QNetworkReply*)), &loop, SLOT(quit())); // connect    loop.exec();    QByteArray byteArray = reply->readAll();    qDebug() << byteArray;    delete reply;    delete m_manager;    return QString(byteArray);}