How to extract <br /> tag from XML (XHTML)

asc7uni · 20 Dec 2020, 14:24

Hello. I have following XML document:

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<table>
<tr>
<td>new<br />line</td>
<td>single line</td>
</tr>
</table>
</body>
</html>

Now I am trying to extract table with following code.

QDomDocument doc;
doc.setContent(html_table);
QDomElement docElem = doc.documentElement();
QDomNodeList tables = docElem.elementsByTagName("table");
for (int i = 0; i < tables.size(); ++i) {
        QDomNode table = tables.item(i);
        QDomElement row = table.firstChildElement("tr");

        while (!row.isNull()) {
            qDebug() << "\trow";
            QDomNodeList cols = row.elementsByTagName("td");
            for (int j = 0; j < cols.size(); ++j) {
                QDomNode col = cols.item(j);
                qDebug() << "\t\tcol" << col.toElement().text();
            }
            row = row.nextSiblingElement("tr");
        }
}

With this I getting following output:

row
    col "newline"
    col "single line"

The question is how to extract <br /> tag and transform it to new line?

Closest I get is to preprocess input before parsing XML and change all <br /> to \n so newline already present in extracted strings.

JonB · 21 Dec 2020, 07:15

@asc7uni
You should be able to get at the <br />. I think you either you shouldn't go col.toElement().text(), or possibly not sure what qDebug() is going to show if it encounters that. Have a poke around in QDomNode col and see what is actually in there before you text() it? I think see my old post at https://forum.qt.io/topic/119756/solved-qdomnode-get-formated-text/2.

asc7uni · J JonB 20 Dec 2020, 14:24

@JonB
Thank you for pointing me in the right direction. It seems I missed completely that the text inside DomNode can be DomNode.
So the following code solves my case:

    QDomNodeList tables = docElem.elementsByTagName("table");
    for (int i = 0; i < tables.size(); ++i) {
            QDomNode table = tables.item(i);
            QDomElement row = table.firstChildElement("tr");

            while (!row.isNull()) {
                qDebug() << "\trow";
                QDomNodeList cols = row.elementsByTagName("td");
                for (int j = 0; j < cols.size(); ++j) {
                    QDomNode col = cols.item(j);
                    qDebug() << "\t\tcol" << col.toElement().text();
// added v
                    QDomNode inside_row = col.firstChild();
                    while (!inside_row.isNull()) {
                        if (inside_row.nodeType() == QDomNode::TextNode) {
                            qDebug() << "\t\t\t inside col"
                                     << inside_row.toText().data();
                        } else {
                            qDebug() << "\t\t\t inside col"
                                     << inside_row.nodeName();
                        }
                        inside_row = inside_row.nextSibling();
                    }
// added ^
                }
                row = row.nextSiblingElement("tr");
            }
    }

And it prints

HTMLTableParser::parse
        row
                col "newline"
                         inside col "new"
                         inside col "br"
                         inside col "line"
                col "single line"
                         inside col "single line"

Which is what I needed.