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之前只写过通过http协议通信#xff0c;没有写过下载http地址中的文件或者文件夹#xff0c;了解一下在QT下如何下载。
其实很简单#xff0c;同使用协议通信相同的是#xff0c;创建QNetworkAccessManager和QNetworkRequest#xff0c;设置QNetworkRequest的url没有写过下载http地址中的文件或者文件夹了解一下在QT下如何下载。
其实很简单同使用协议通信相同的是创建QNetworkAccessManager和QNetworkRequest设置QNetworkRequest的url通过get请求接收QNetworkReply中数据利用downloadProgress信号接收每次下载下来的内容直到下载完成。
代码如下 .pro
主要是加上network模块
#-------------------------------------------------
#
# Project created by QtCreator 2023-10-26T18:29:32
#
#-------------------------------------------------QT core gui networkgreaterThan(QT_MAJOR_VERSION, 4): QT widgetsTARGET load_http_file
TEMPLATE app# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as 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 you use 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_BEFORE0x060000 # disables all the APIs deprecated before Qt 6.0.0SOURCES \main.cpp \widget.cpp \HEADERS \widget.h \FORMS \widget.ui界面 widget.h
#ifndef WIDGET_H
#define WIDGET_H#include QWidget
#include QFile
#include QUrl
#include QNetworkReply
#include QNetworkRequest
#include QNetworkAccessManager
#include QEventLoop
#include QTimernamespace Ui {
class Widget;
}class Widget : public QWidget
{Q_OBJECTpublic:explicit Widget(QWidget *parent 0);~Widget();bool downloadFile(QString url);
private slots:void on_load_zip_clicked();private:Ui::Widget *ui;private:bool flag_download false;
};#endif // WIDGET_H
widget.cpp
#include widget.h
#include QDir
#include QThreadWidget::Widget(QWidget *parent) :QWidget(parent),ui(new Ui::Widget)
{}Widget::~Widget()
{delete ui;
}void Widget::on_load_zip_clicked()
{downloadFile(ui-lineEdit_url-text());
}bool Widget::downloadFile(QString url)
{if(flag_download){qDebug()有正在下载中的文件已停止当前下载。;return false;}int timeout 1000 * 60; //* 3;QString path 3D;QDir dir(path);if(!dir.exists()){if(!dir.mkdir(dir.absolutePath())){qDebug()创建3D文件夹失败;return false;}}path path / url.section(/,-1,-1);qDebug()url:url path:path;QFile file(path);if (!file.open(QIODevice::WriteOnly)){qDebug()打开待下载文件失败;return false;}flag_download true;QNetworkAccessManager networkManager;QNetworkRequest request;request.setUrl(QUrl(url));QNetworkReply *reply networkManager.get(request);QTimer timer;QEventLoop eventLoop;connect(reply, QNetworkReply::downloadProgress, [, file, timer](qint64 bytesReceived,qint64 bytesTotal){qDebug()当前下载的文件大小bytesReceived 总文件大小bytesTotal;if (timer.isActive())timer.start(timeout);file.write(reply-readAll());});connect(reply, QNetworkReply::finished, timer, QTimer::stop);connect(reply, QNetworkReply::finished, eventLoop, QEventLoop::quit);connect(timer, QTimer::timeout, eventLoop, QEventLoop::quit);timer.start(timeout);eventLoop.exec();//QEventLoop::ExcludeUserInputEventsflag_download false;if (reply-error() ! QNetworkReply::NoError){qDebug()请求失败失败原因reply-error();file.close();delete reply;return false;}if(timer.isActive()){qDebug()请求超时;timer.stop();file.close();delete reply;return false;}qDebug()下载3D文件成功;file.close();delete reply;return true;
}
