使用 QNetworkAccessManager 在 QT 中的 HTTP POST 请求
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【中文标题】使用 QNetworkAccessManager 在 QT 中的 HTTP POST 请求【英文标题】:HTTP POST request in QT using QNetworkAccessManager 【发布时间】:2020-03-28 17:20:18 【问题描述】:我必须向我的服务器发送一个数据字符串,我正在拼命尝试使用 QNetworkAccessManager,但是几个星期都没有成功,有人可以帮忙!
我的代码如下。
它可以编译,但是当我运行它时,我得到一个空回复。
QT 应用程序输出:我得到一个空回复
当我检查接收文本的服务器上的日志文件时,它是空的。
我尝试使用 POSTMAN,它工作正常。
请检查下图,它显示了我尝试使用 POSTMAN 时的结果
使用 POSTMAN 的结果
我在下面包含了我的代码,请帮忙。
主程序
#include <QCoreApplication>
#include <stdio.h>
#include <string>
#include <QtDebug>
#include <QObject>
#include <httpmanager.h>
QByteArray dataString ="A=##1802201049565471101000000N0526.874000E07256.4380000101035070#&11397002170466466466466466&12208004230370336441514488!~~~0";
using namespace std;
int main(void)
HTTPmanager myHttpManager;
while(1)
myHttpManager.postData("A==##1802201049565471101000000N0526.874000E07256.4380000101035070#&11397002170466466466466466&12208004230370336441514488!~~~0");
Sleep(1000);
//main loop ends
return 0;
httpmanager.h--------
#ifndef HTTPMANAGER_H
#define HTTPMANAGER_H
#include <QObject>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QUrl>
class HTTPmanager : public QObject
Q_OBJECT
public:
HTTPmanager();
~HTTPmanager();
void postData(QString str);
private:
QNetworkAccessManager * manager;
QNetworkRequest request;
QNetworkReply *reply;
private slots:
void replyFinished(QNetworkReply *rep);
;
#endif // HTTPMANAGER_H
httpmanager.cpp-------------
#include "httpmanager.h"
HTTPmanager::HTTPmanager()
HTTPmanager::~HTTPmanager()
delete manager; manager = nullptr;
void HTTPmanager::postData(QString str)
QByteArray data = str.toUtf8();
QUrl url;
manager = new QNetworkAccessManager(this);
url.setScheme("http");
url.setHost("test.vivcorefmms.com");
url.setPath("/node/filter_data");
request.setUrl(url);
request.setRawHeader("Content-Type", "application/x-www-form-urlencoded");
request.setRawHeader("Content-Length", QByteArray::number(data.size()));
//connect(reply, SIGNAL(readyRead()),this, SLOT(slotReadyRead()));
connect(manager, SIGNAL(finished(QNetworkReply*)),this, SLOT(replyFinished(QNetworkReply*)));
//connect(reply, SIGNAL(sslErrors(QList<QSslError>)),this, SLOT(slotSslErrors(QList<QSslError>)));
//connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
//loop.exec();
reply = manager->post(request,data);
QByteArray bts = reply->readAll();
QString tmp(bts);
qDebug() << "Reply:"<<tmp;
void HTTPmanager::replyFinished(QNetworkReply *rep)
QByteArray bts = rep->readAll();
QString str(bts);
qDebug() << "Reply:"<<str;
【问题讨论】:
【参考方案1】:您似乎不知道以下概念:
Qt Network 像所有 Qt 模块一样异步工作,所以不要考虑同步获取信息。
Qt 需要一个事件循环,在这种情况下 QCoreApplication 就足够了。
如果您想执行周期性任务,那么您应该使用 QTimer 而不是带有 Sleep 的 while 循环。
综合以上,解决办法是:
httpmanager.h
#ifndef HTTPMANAGER_H
#define HTTPMANAGER_H
#include <QObject>
class QNetworkReply;
class QNetworkAccessManager;
class HTTPManager : public QObject
Q_OBJECT
public:
HTTPManager(QObject *parent=nullptr);
~HTTPManager();
void postData(QString str);
private Q_SLOTS:
void replyFinished(QNetworkReply *rep);
private:
QNetworkAccessManager * manager;
QNetworkReply *reply;
;
#endif // HTTPMANAGER_H
httpmanager.cpp
#include "httpmanager.h"
#include <QNetworkAccessManager>
#include <QNetworkReply>
HTTPManager::HTTPManager(QObject *parent)
: QObject(parent), manager(new QNetworkAccessManager(this))
connect(manager, &QNetworkAccessManager::finished,this, &HTTPManager::replyFinished);
HTTPManager::~HTTPManager()
void HTTPManager::postData(QString str)
QNetworkRequest request;
QByteArray data = str.toUtf8();
QUrl url;
url.setScheme("http");
url.setHost("test.vivcorefmms.com");
url.setPath("/node/filter_data");
request.setUrl(url);
request.setRawHeader("Content-Type", "application/x-www-form-urlencoded");
manager->post(request, data);
void HTTPManager::replyFinished(QNetworkReply *rep)
QByteArray bts = rep->readAll();
QString str = QString::fromUtf8(bts);
qDebug().noquote() << "Reply:"<<str;
rep->deleteLater();
main.cpp
#include "httpmanager.h"
#include <QCoreApplication>
#include <QTimer>
int main(int argc, char *argv[])
QCoreApplication a(argc, argv);
HTTPManager manager;
QTimer timer;
timer.setInterval(1000);
QObject::connect(&timer, &QTimer::timeout, [&manager]()
manager.postData("A==##1802201049565471101000000N0526.874000E07256.4380000101035070#&11397002170466466466466466&12208004230370336441514488!~~~0");
);
timer.start();
return a.exec();
Reply: <head><title>Not Acceptable!</title></head><body><h1>Not Acceptable!</h1><p>An appropriate representation of the requested resource could not be found on this server. This error was generated by Mod_Security.</p></body></html>
这是因为缺少用户代理,因此将其修改为:
request.setRawHeader("Content-Type", "application/x-www-form-urlencoded");
request.setRawHeader("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.47 Safari/537.36");
manager->post(request, data);
获得以下内容:
Reply: <!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Database Error</title>
<style type="text/css">
::selection background-color: #E13300; color: white;
::-moz-selection background-color: #E13300; color: white;
body
background-color: #fff;
margin: 40px;
font: 13px/20px normal Helvetica, Arial, sans-serif;
color: #4F5155;
a
color: #003399;
background-color: transparent;
font-weight: normal;
h1
color: #444;
background-color: transparent;
border-bottom: 1px solid #D0D0D0;
font-size: 19px;
font-weight: normal;
margin: 0 0 14px 0;
padding: 14px 15px 10px 15px;
code
font-family: Consolas, Monaco, Courier New, Courier, monospace;
font-size: 12px;
background-color: #f9f9f9;
border: 1px solid #D0D0D0;
color: #002166;
display: block;
margin: 14px 0 14px 0;
padding: 12px 10px 12px 10px;
#container
margin: 10px;
border: 1px solid #D0D0D0;
box-shadow: 0 0 8px #D0D0D0;
p
margin: 12px 15px 12px 15px;
</style>
</head>
<body>
<div id="container">
<h1>A Database Error Occurred</h1>
<p>Error Number: 1048</p><p>Column 'node_id' cannot be null</p><p>INSERT INTO `node_info` (`node_info_id`, `node_id`, `message_id`, `gsm`, `wifi`, `gprs`, `_3g`, `bluetooth`, `gps`, `emergency_code`, `env_temperature`, `env_humidity`, `env_pressure`, `gps_speed`, `gps_latitude`, `gps_longitude`, `date`, `time`, `number_of_compartment`, `number_of_dispense`, `sys_date`, `sys_time`) VALUES ('', NULL, '654', '7', '0', '1', '1', '1', '0', '0', '03', '507', '0101', '0', NULL, NULL, '#18022', '010495', 15, '', '2020-03-28', '23:31:10')</p><p>Filename: models/Model_master.php</p><p>Line Number: 156</p> </div>
</body>
</html>
消息指出错误:
Error Number: 1048
Column 'node_id' cannot be null
INSERT INTO `node_info` (`node_info_id`, `node_id`, `message_id`, `gsm`, `wifi`, `gprs`, `_3g`, `bluetooth`, `gps`, `emergency_code`, `env_temperature`, `env_humidity`, `env_pressure`, `gps_speed`, `gps_latitude`, `gps_longitude`, `date`, `time`, `number_of_compartment`, `number_of_dispense`, `sys_date`, `sys_time`) VALUES ('', NULL, '654', '7', '0', '1', '1', '1', '0', '0', '03', '507', '0101', '0', NULL, NULL, '#18022', '010495', 15, '', '2020-03-28', '23:18:26')
Filename: models/Model_master.php
Line Number: 156
其中显示发送的数据似乎不符合处理导致的错误,即A==##1802201049565471101000000N0526.874000E07256.4380000101035070#&11397002170466466466466466&12208004230370336441514488!~~~0
似乎格式不正确
【讨论】:
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