如何使用Qt获取重定向页面的html代码? [英] How can I use Qt to get html code of the redirected page?
问题描述
我尝试使用Qt从以下网址下载html代码:
I'm trying to use Qt to download the html code from the following url:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=核苷酸& cmd =搜索& term = AB100362
此网址将重定向到
www.ncbi.nlm.nih.gov/nuccore/27884304
www.ncbi.nlm.nih.gov/nuccore/27884304
我试着这样做,但我不能得到任何东西。
它适用于某些网页,如www.google.com,但不适用于此NCBI页面。是否有任何方式获取此页面?
I try to do it by following way, but I cannot get anything. it works for some webpage such as www.google.com, but not for this NCBI page. is there any way to get this page??
QNetworkReply::NetworkError downloadURL(const QUrl &url, QByteArray &data)
{
QNetworkAccessManager manager;
QNetworkRequest request(url);
QNetworkReply *reply = manager.get(request);
QEventLoop loop;
QObject::connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
loop.exec();
if (reply->error() != QNetworkReply::NoError)
{
return reply->error();
}
data = reply->readAll();
delete reply;
return QNetworkReply::NoError;
}
void GetGi()
{
int pos;
QString sGetFromURL = "http://www.ncbi.nlm.nih.gov/entrez/query.fcgi";
QUrl url(sGetFromURL);
url.addQueryItem("db", "nucleotide");
url.addQueryItem("cmd", "search");
url.addQueryItem("term", "AB100362");
QByteArray InfoNCBI;
int errorCode = downloadURL(url, InfoNCBI);
if (errorCode != 0 )
{
QMessageBox::about(0,tr("Internet Error "), tr("Internet Error %1: Failed to connect to NCBI.\t\nPlease check your internect connection.").arg(errorCode));
return "ERROR";
}
}
推荐答案
该网页似乎有重新导向。
That page appears to have a redirect.
从Qt docs for 4.6:
From the Qt docs for 4.6:
注意:当HTTP协议返回
重定向时,不会报告错误。
您可以使用
QNetworkRequest :: RedirectionTargetAttribute
属性检查是否存在重定向
。
Note: When the HTTP protocol returns a redirect no error will be reported. You can check if there is a redirect with the QNetworkRequest::RedirectionTargetAttribute attribute.
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