qt爬虫下载图片.zip

#include "widget.h" #include "ui_widget.h" #include <QJsonDocument> #include <QJsonObject> #include <QJsonArray> #include <QDebug> #include <QUrl> #include <QNetworkReply> #include <QNetworkAccessManager> #include <QFuture> #include <QtConcurrent> #include <QMessageBox> #define debug qDebug()<< QStringList Widget::failList; Widget::Widget(QWidget *parent) : QWidget(parent) , ui(new Ui::Widget) { ui->setupUi(this); } Widget::~Widget() { delete ui; } void Widget::getHttpData(const QString & urlString) { QUrl url = QUrl::fromUserInput(urlString.toUtf8()); if(!url.isValid()) { failList << urlString; return; } QNetworkRequest request; request.setUrl(url); QNetworkAccessManager manager; QNetworkReply * reply_ = manager.get(request); connect(reply_, QOverload<QNetworkReply::NetworkError>::of(&QNetworkReply::error),[&](QNetworkReply::NetworkError code) { switch(static_cast<int>(code)) { case QNetworkReply::ConnectionRefusedError: debug "远程服务器拒绝连接（服务器不接受请求）"; break; case QNetworkReply::HostNotFoundError: debug "找不到远程主机名（无效的主机名）"; break; case QNetworkReply::TimeoutError: debug "与远程服务器的连接超时"; break; default: break; } }); QEventLoop eventLoop2; connect(reply_, &QNetworkReply::finished, &eventLoop2, &QEventLoop::quit); eventLoop2.exec(QEventLoop::ExcludeUserInputEvents); QByteArray data = reply_->readAll(); if(data.isEmpty()) { failList << urlString; return; } QRegExp exp("[^/]+\.(png|jpg)$"); exp.setMinimal(false); int pos = 0; QString fileName; while ((pos = exp.indexIn(urlString , pos)) != -1) { pos += exp.matchedLength(); fileName = exp.cap(0); } QPixmap pixmap; pixmap.loadFromData(data); pixmap.save("pic/" + fileName); } void Widget::on_pushButton_clicked() { QString dataInfo = ui->textEdit->toPlainText().trimmed(); QJsonDocument jsonDocument = QJsonDocument::fromJson(dataInfo.toUtf8().data()); QJsonArray array = jsonDocument.object()["data"].toObject()["items"].toArray(); std::for_each(array.begin(),array.end(),[this](const QJsonValue & value) { urlList << value.toObject()["picUrl"].toString(); }); if(!urlList.isEmpty()) { debug "图片数量：" << urlList.size(); failList.clear(); QFuture<void> f = QtConcurrent::map(urlList,&Widget::getHttpData); f.waitForFinished(); QMessageBox::information(this,"提示","全部下载完成"); if(!failList.isEmpty()) { debug "以下图片下载失败："<<endl<<failList; } } else { debug "没有图片"; } }