How can I manage that my XML reader, searching for attributes with a special parent element?
e.g. my XML file:
<section name="aPoly">
<attribute key="id" type="int">1</attribute>
<attribute key="label" type="String">2</attribute>
<section name="graphic">
<attribute key="x" type="double">780.0</attribute>
<attribute key="y" type="double">240.0</attribute>
<attribute key="w" type="double">78.0</attribute>
<attribute key="h" type="double">78.0</attribute>
</section>
</section>
...
...
<section name="line">
<attribute key="source" type="int">0</attribute>
<attribute key="target" type="int">4</attribute>
<section name="graphic">
<attribute key="fill" type="String">#000000</attribute>
<section name="poly">
<section name="pt">
<attribute key="x" type="double">377.0</attribute>
<attribute key="y" type="double">240.0</attribute>
</section>
<section name="pt">
<attribute key="x" type="double">570.0</attribute>
<attribute key="y" type="double">240.0</attribute>
</section>
<section name="pt">
<attribute key="x" type="double">570.0</attribute>
<attribute key="y" type="double">330.0</attribute>
</section>
</section>
</section>
</section>
There are multiple attributes with key = "x". I want to save the x values of section name="aPoly" in one array and the x values of section name="line" into another array.
I am searching for attributes and save it to a QVector. (Search all X attributes).
QDomElement root = document.documentElement();
QDomNodeList key = root.elementsByTagName("attribute");
for(int i = 0; i < key.count(); i++)
{
QDomNode keynode = key.at(i);
if(keynode.isElement())
{
QDomElement att = keynode.toElement();
if (att.attribute("key") == "x"){
xarray.push_back(att.text());
}else if (att.attribute("key") =="y") {
yarray.push_back(att.text());
}...
What can I change to achieve this?
Edit:
Why he dont fill my array? Its always empty? Where is my mistake?
QXmlQuery query;
if (query.setFocus(&file))
{
query.setQuery(QString("section/section/section[@name='aPoly']/section/attribute[@key='x']"));
if (query.isValid())
{
QString result;
query.evaluateTo(&result);
QDomDocument dom;
dom.setContent(QString("<Data>%1</Data>").arg(result));
QDomNodeList children = dom.documentElement().childNodes();
for (int i = 0; i < children.count(); i++)
{
QDomNode nod = children.at(i);
if(nod.isElement())
{
QDomElement art = nod.toElement();
Newarray.push_back(art.text());
}
}
}
}
qDebug() << "\r\nNewArray : " <<QList<QString>::fromVector(Newarray);
You can use XQuery for this. XPath similar to following can be used for your purpose assuming section elements are inside a sections element and it is the root of your xml document.
"sections/section[@name='aPoly']/attribute[@key='x']"
Eg.
QXmlQuery query;
if (query.setFocus(yourXmlString)
{
query.setQuery("sections/section[@name='aPoly']/attribute[@key='x']");
if (query.isValid())
{
QString result;
query.evaluateTo(&result);
QDomDocument dom;
dom.setContent(QString("<Data>%1</Data>").arg(result));
QDomNodeList children = dom.documentElement().childNodes();
for (int i = 0; i < children.count(); ++i)
{
//children.at(i) is an attribute element which matches your criteria.
}
}
}