QT利用QNetworkAccessManager下载文件

在这里利用QNetworkAccessManager来实现下载文件，经测试，可以使用http或者ftp都可以使用，别的还未测试

此处使用QT 4.8.6

首先记得在.pro文件加入network

QT       += core gui network

//此处用来实现进度条显示

void Widget::downloadProgress(qint64 a,qint64 b)
{
    f->write(reply->readAll());
    ui->progressBar->setMaximum(b);
    ui->progressBar->setValue(a);
}

//此处当下载完毕，用来刷新和关闭文件

void Widget::onFinished(QNetworkReply * reply)//reply用于接收消息
{
    qDebug() << "Your thing had finished downloading.";
    f->flush();
    f->close();
    reply->deleteLater();
}

//此处用来下载和删除文件

void Widget::on_btnDownload_clicked()
{
    QFileInfo info("http://tupian.enterdesk.com/2012/0606/gha/10/11285966_1334673509285.jpg");

    f = new QFile(info.fileName());
    f->open(QIODevice::WriteOnly);
    reply = manager->get(QNetworkRequest(QUrl("http://tupian.enterdesk.com/2012/0606/gha/10/11285966_1334673509285.jpg")));
    connect(reply,SIGNAL(downloadProgress(qint64,qint64)),this,SLOT(downloadProgress(qint64,qint64)));
}



void Widget::on_btnDel_clicked()
{
    QFileInfo info("http://tupian.enterdesk.com/2012/0606/gha/10/11285966_1334673509285.jpg");

    f = new QFile(info.fileName());

    f->remove();
}

具体的代码可以在这里下载

Qt利用QNetworkAccessManager下载文件