Qt-获得网络状态(testNetOnIine)(Qt5.14.2+win10)

相关资料：

https://blog.csdn.net/qq_43658314/article/details/109814071   QT学习记录 --- 利用QNetworkConfigurationManager检测网络连接变化

https://www.cnblogs.com/itrena/p/5938377.html      QHostInfo类为主机名查找提供了静态函数。

https://www.cnblogs.com/liushui-sky/articles/9474478.html     Qt判断网络连接

 

实例代码：

testNetOnIine.pro

QT       += core gui
QT       += network

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

CONFIG += c++11

# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
    main.cpp \
    mainwindow.cpp

HEADERS += \
    mainwindow.h

FORMS += \
    mainwindow.ui

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

main.cpp

#include "mainwindow.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

#include <QNetworkConfigurationManager>
#include <QHostInfo>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();

    void on_pushButton_2_clicked();
    void onLookupHost(QHostInfo host);

private:
    Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

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

    setWindowTitle(QStringLiteral("获得网络状态"));
}

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

void MainWindow::on_pushButton_clicked()
{
    QNetworkConfigurationManager mgr;
    if (mgr.isOnline())
    {
        ui->label_2->setText(QStringLiteral("有连接"));
    }
    else
    {
        ui->label_2->setText(QStringLiteral("无连接"));
    }
}

void MainWindow::on_pushButton_2_clicked()
{
    QHostInfo::lookupHost("www.baidu.com", this, SLOT(onLookupHost(QHostInfo)));
}

void MainWindow::onLookupHost(QHostInfo host)
{
    if (host.error() != QHostInfo::NoError)
    {
        qDebug() << "Lookup failed:" << host.errorString();
        ui->label_4->setText(QStringLiteral("无外网"));
    }
    else{
        ui->label_4->setText(QStringLiteral("有外网"));
    }
}

mainwindow.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>329</width>
    <height>155</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralwidget">
   <widget class="QPushButton" name="pushButton">
    <property name="geometry">
     <rect>
      <x>170</x>
      <y>20</y>
      <width>80</width>
      <height>20</height>
     </rect>
    </property>
    <property name="text">
     <string>获得状态</string>
    </property>
   </widget>
   <widget class="QPushButton" name="pushButton_2">
    <property name="geometry">
     <rect>
      <x>170</x>
      <y>60</y>
      <width>80</width>
      <height>20</height>
     </rect>
    </property>
    <property name="text">
     <string>获得外网</string>
    </property>
   </widget>
   <widget class="QLabel" name="label">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>20</y>
      <width>54</width>
      <height>12</height>
     </rect>
    </property>
    <property name="text">
     <string>网络状态：</string>
    </property>
   </widget>
   <widget class="QLabel" name="label_2">
    <property name="geometry">
     <rect>
      <x>80</x>
      <y>20</y>
      <width>54</width>
      <height>12</height>
     </rect>
    </property>
    <property name="text">
     <string>无</string>
    </property>
   </widget>
   <widget class="QLabel" name="label_3">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>60</y>
      <width>54</width>
      <height>12</height>
     </rect>
    </property>
    <property name="text">
     <string>互 联 网：</string>
    </property>
   </widget>
   <widget class="QLabel" name="label_4">
    <property name="geometry">
     <rect>
      <x>80</x>
      <y>60</y>
      <width>54</width>
      <height>12</height>
     </rect>
    </property>
    <property name="text">
     <string>无</string>
    </property>
   </widget>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>329</width>
     <height>22</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>