QT5 之HTTP -GET/POST请求

1、添加network模块

QT       += core gui network

2、头文件添加

#include
#include 
#include
#include//json
#include  //https
#include 

3、初始化HTTP的QNetworkAccessManager及建立连接信号槽

//声明  .h文件
private slots:
    void finishedSlot(QNetworkReply *reply);

//初始化
    m_accessManager = new QNetworkAccessManager();
    QObject::connect(m_accessManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(finishedSlot(QNetworkReply*)));
//接收函数
void MainWindow::finishedSlot(QNetworkReply *reply)
{
     if (reply->error() == QNetworkReply::NoError)
     { = reply->readAll();
         QString str(bytes);
         QByteArray bytes
         qDebug()<attribute(QNetworkRequest::HttpStatusCodeAttribute);
         //statusCodeV是HTTP服务器的相应码，reply->error()是Qt定义的错误码，可以参考QT的文档
         qDebug( "found error ....code: %d %d\n", statusCodeV.toInt(), (int)reply->error());
         qDebug(qPrintable(reply->errorString()));
     }
     reply->deleteLater();
}

4、简单的get 实现代码

void MainWindow::on_pushButton_clicked()
{
    qDebug("get");
    QNetworkRequest request;
    request.setUrl(QUrl("http://wthrcdn.etouch.cn/weather_mini?citykey=101020100"));
    m_accessManager->get(request);

}

实验现象："{\"data\":{\"yesterday\":{\"date\":\"2日星期日\",\"high\":\"高温 35℃\",\"fx\":\"南风\",\"low\":\"低温 28℃\",\"fl\":\"\",\"type\":\"多云\"},\"city\":\"上海\",\"forecast\":[{\"date\":\"3日星期一\",\"high\":\"高温 35℃\",\"fengli\":\"\",\"low\":\"低温 28℃\",\"fengxiang\":\"南风\",\"type\":\"多云\"},{\"date\":\"4日星期二\",\"high\":\"高温 32℃\",\"fengli\":\"\",\"low\":\"低温 28℃\",\"fengxiang\":\"东南风\",\"type\":\"小雨\"},{\"date\":\"5日星期三\",\"high\":\"高温 34℃\",\"fengli\":\"\",\"low\":\"低温 28℃\",\"fengxiang\":\"南风\",\"type\":\"小雨\"},{\"date\":\"6日星期四\",\"high\":\"高温 35℃\",\"fengli\":\"\",\"low\":\"低温 28℃\",\"fengxiang\":\"南风\",\"type\":\"阴\"},{\"date\":\"7日星期五\",\"high\":\"高温 35℃\",\"fengli\":\"\",\"low\":\"低温 28℃\",\"fengxiang\":\"西南风\",\"type\":\"阴\"}],\"ganmao\":\"感冒低发期，天气舒适，请注意多吃蔬菜水果，多喝水哦。\",\"wendu\":\"29\"},\"status\":1000,\"desc\":\"OK\"}"

因为url是一个天气你相关的接口，所以返回的是天气信息

5、简单POST请求，POTS 请求自动了参数

void MainWindow::on_pushButton_2_clicked()
{
    QNetworkRequest request;
    request.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("application/json")); //设置数据类型
    request.setUrl(QUrl("你自己的URL"));//注意填写自己相关URL
    QJsonObject obj;
    obj.insert("SoftVersion", "V1.0");
    QByteArray byteArray = QJsonDocument(obj).toJson(QJsonDocument::Compact);
    QString str(byteArray);
    qDebug()<post(request,byteArray);
}

6、简单https请求  

https 需要下载https库，因为需要Openssl支持，使用SSL进行认证，所以需要对应的库文件 libeay32.dll和ssleay32.dll。需要下载libeay32.dll 和 ssleay32.dll两个库文件，将这两个库文件拷贝到程序生成目录下（即生成exe的同级目录）或者拷贝到QtNetwork模块的库文件目录中，在 http://slproweb.com/products/Win32OpenSSL.html 中下载 Win32 OpenSSL进行安装，将bin目录下面的库拷贝出来放到生成程序exe同级目录下即可。

void MainWindow::on_pushButton_3_clicked()
{
    QNetworkRequest request;
    QSslConfiguration conf = request.sslConfiguration();
    conf.setPeerVerifyMode(QSslSocket::VerifyNone);
    conf.setProtocol(QSsl::TlsV1SslV3);
    request.setSslConfiguration(conf);
    request.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("application/json")); //设置数据类型

    request.setUrl(QUrl("自己的URL"));

    QJsonObject obj;
    obj.insert("SoftVersion", "V1.0");
    QByteArray byteArray = QJsonDocument(obj).toJson(QJsonDocument::Compact);
   // qDebug() << "user Info" << obj << endl;
    QString str(byteArray);
   // qDebug()<post(request,byteArray);
}