QT平台http请求开发实例

【核心代码】

#include "widget.h"
#include "ui_widget.h"
#include <QNetworkRequest>
#include <QJsonObject>
#include <QJsonDocument>

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    naManager = new QNetworkAccessManager(this);
    // 绑定信号槽，处理来自服务器的响应
    connect(naManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(requestFinished(QNetworkReply*)));
}

Widget::~Widget()
{
    delete ui;
}

// 向服务器发送Http Post请求
void Widget::on_pushButton_clicked()
{
    QNetworkRequest request;    // request对象管理Post请求

    request.setUrl(QUrl("http://192.168.43.200/cgi-bin/a.cgi"));
//    naManager->get(request);

    QJsonObject qjo;
    qjo.insert("m", 16);
    qjo.insert("n", 17);
    //post请求的数据是Json格式。首先创建QJsonObject对象，并插入数据。
    QByteArray  httpData;
    QJsonDocument httpDocum;
    httpDocum.setObject(qjo);
    httpData = httpDocum.toJson(QJsonDocument::Compact);

    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");  // x-www-form-urlencoded
    request.setHeader(QNetworkRequest::ContentLengthHeader, httpData.length());

    naManager->post(request, httpData);
}

void Widget::requestFinished(QNetworkReply* reply) {
    // 获取http状态码
    QVariant statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute);
    if(statusCode.isValid())
        qDebug() << "status code=" << statusCode.toInt();

    QVariant reason = reply->attribute(QNetworkRequest::HttpReasonPhraseAttribute).toString();
    if(reason.isValid())
        qDebug() << "reason=" << reason.toString();

    QNetworkReply::NetworkError err = reply->error();
    if(err != QNetworkReply::NoError) {
        qDebug() << "Failed: " << reply->errorString();
    }
    else {
        // 获取返回内容
        QByteArray ba = reply->readAll();
        QJsonDocument jd = QJsonDocument::fromJson(ba);
        QJsonObject jo = jd.object();
        qDebug() << jo["m"] << jo["n"];
    }
}