XML: accessing deep nodes

[mentalmushroom]

Hello. Is there a way to access XML nodes with something like this:

domDoc.elementsByTagName("methodResponse/params/param/value/struct/member")

domDoc.elementsByTagName("methodResponse/params/param/value/struct/member")

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instead of

QDomElement elem = domDoc.firstChildElement("methodResponse").firstChildElement("params").firstChildElement("param").firstChildElement("value").firstChildElement("struct").firstChildElement("member")

QDomElement elem = domDoc.firstChildElement("methodResponse").firstChildElement("params").firstChildElement("param").firstChildElement("value").firstChildElement("struct").firstChildElement("member")

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Here follows the sample XML document. I need to get access to all 'member' nodes.

<?xml version="1.0" encoding="utf-8"?>
<methodResponse>
<params>
 <param>
  <value>
   <struct>
    <member>
     <name>token</name>
     <value>
      <string>532236bdf362493h5</string>
     </value>
    </member>
    <member>
     <name>status</name>
     <value>
      <string>200 OK</string>
     </value>
    </member>
    <member>
     <name>seconds</name>
     <value>
      <double>0.008</double>
     </value>
    </member>
   </struct>
  </value>
 </param>
</params>
</methodResponse>

<?xml version="1.0" encoding="utf-8"?>
<methodResponse>
<params>
 <param>
  <value>
   <struct>
    <member>
     <name>token</name>
     <value>
      <string>532236bdf362493h5</string>
     </value>
    </member>
    <member>
     <name>status</name>
     <value>
      <string>200 OK</string>
     </value>
    </member>
    <member>
     <name>seconds</name>
     <value>
      <double>0.008</double>
     </value>
    </member>
   </struct>
  </value>
 </param>
</params>
</methodResponse>

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[wysota]

See QXmlQuery.

[ollerei]

Or You can use XPath to do the Query

[mentalmushroom]

Ok, thanks. Some another question... I receive xml from the network. It seems like QXmlQuery allows to use QNetworkReply in bindVariable method, e.g.

query.bindVariable("MyXml", reply);

query.bindVariable("MyXml", reply);

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But it doesn't work: evaluateTo hangs up for 5-10 seconds, then I see "First-chance exception at 0x760eb727 in SnelNL.exe: Microsoft C++ exception: bool at memory location 0x0034c20f.." in the output window.

However if I read data to QByteArray and create QBuffer with this data, query works fine.

Is it possible to use QNetworkReply directly in QXmlQuery::bindVariable as XML source?

[wysota]

Why not just use the doc() directive in the query itself?

QXmlQuery query;
query.setQuery("doc(http://www.qtcentre.org/index.php)/html/body/whatever");

QXmlQuery query;
query.setQuery("doc(http://www.qtcentre.org/index.php)/html/body/whatever");

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[mentalmushroom]

I need to make a post request in order to receive a reply from server

[wysota]

In that case use QXmlQuery::setFocus() and pass it the network reply you receive. Just make sure you do it only after the data you expect has arrived.

[mentalmushroom]

Thanks, but still the same problem when I pass a reply as QIODevice. Below is the slot that is connected to QNetworkAccessManager::finished signal, so all the data must be arrived, I think.

void MyClass::authenticationFinished(QNetworkReply *reply)
{
 QXmlQuery query;
 query.setFocus(reply);
 query.setQuery("methodResponse/params/param/value/struct/member[name=\"token\"]/value/string(string)");
 // ...
}

void MyClass::authenticationFinished(QNetworkReply *reply)
{
 QXmlQuery query;
 query.setFocus(reply);
 query.setQuery("methodResponse/params/param/value/struct/member[name=\"token\"]/value/string(string)");
 // ...
}

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The following code works fine:

void MyClass::authenticationFinished(QNetworkReply *reply)
{
 QXmlQuery query;
 query.setFocus(reply->readAll()); // !pass the string
 query.setQuery("methodResponse/params/param/value/struct/member[name=\"token\"]/value/string(string)");
 // ...
}

void MyClass::authenticationFinished(QNetworkReply *reply)
{
 QXmlQuery query;
 query.setFocus(reply->readAll()); // !pass the string
 query.setQuery("methodResponse/params/param/value/struct/member[name=\"token\"]/value/string(string)");
 // ...
}

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