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POC++ Qt get HTTP headers from QNetworkRequest
primarykey
Id
16086077
data
AcceptedAnswerId
16086198
AnswerCount
2
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2013-04-18T14:43:38.967
FavoriteCount
0
LastActivityDate
2013-12-05T18:53:03.440
LastEditDate
2017-05-23T10:29:23.917
LastEditorUserId
-1
OwnerUserId
1726690
ParentId
0
PostTypeId
1
Score
0
ViewCount
4032
LastEditorDisplayName
text
Body
I am developing a Qt C++ application. I need to download some files (which can be large) and show downloading progress to user. To perform this task, I use this code: <pre><code>QNetworkAccessManager* networkManager = new QNetworkAccessManager(); QNetworkRequest request(fileUrl); //fileUrl is a QUrl variable QVariant responseLength = request.header(QNetworkRequest::ContentLengthHeader); int fileSize = responseLength.toInt(); ui->progressBar->setMaximum(fileSize); QNetworkReply reply = networkManager->get(request); QObject::connect(reply, SIGNAL(downloadProgress(qint64,qint64)), this, SLOT(downloadProgressChanged(qint64,qint64))); </code></pre> Where <code>downloadProgressChanged</code> is a slot with this code: <pre><code>void downloadProgressChanged(qint64 downloaded, qint64 total) { ui->progressBar->setValue(ui->progressBar->value() + 1); ui->labelProgress->setText(QString::number((downloaded / 1024))); } </code></pre> (I use QProgressBar named <code>progressBar</code> to show progress and QLabel named <code>labelProgress</code> to show downloaded kilobytes). My problem is that I can't access Content-Length header (<code>int fileSize</code> value is 0) and so I am not able to show the progress of the operation. I checked HTTP headers on my web-server - Content-Length works fine. In <a href="https://stackoverflow.com/questions/6778118/reading-http-headers">this SO question</a> I read that I can use <code>QNetworkReply::metaDataChanged()</code> signal, but how can I use it to show progress? Documentation says that the signal can be emitted when downloading has been already started, but I need to get header content before downloading will start - to set up my progressBar.
Tags
<c++><qt><http-headers><qnetworkaccessmanager>
Title
C++ Qt get HTTP headers from QNetworkRequest
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1. PO
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 PTAnswer
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1. This table or related slice is empty.
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1. PTQuestion
UserLastEditorUserId
1. USCommunity
UserOwnerUserId
1. USahawkthomas
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1. PL
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1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
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 PTAnswer
2. PO
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