Format XML file in c++ or Qt

Question

I have an XML file where outputs are not getting formatted. That means all the outputs are in a single line but I want to break it tag by tag.

For e.g. -

<?xml version="1.0" encoding="UTF-8" standalone="no" ?><Analyser>   <JointDetails>              <Details><StdThickness> T </StdThickness><Thickness_num> 0.032 </Thickness_num></Details>   </JointDetails></Analyser>

But i want to do it like this ::

<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
<Analyser>  
 <JointDetails>
   <Details>
<StdThickness> T </StdThickness>
<Thickness_num> 0.032 </Thickness_num>
</Details> 
  </JointDetails>
</Analyser>

Please don't suggest to do it while writing the XML file because this XML file is already there but now I have to format it as mentioned above.

Answer 1

Using a QXmlStreamReader and QXmlStreamWriter should do what you want. QXmlStreamWriter::setAutoFormatting(true) will format the XML on different lines and use the correct indentation. With QXmlStreamReader::isWhitespace() you can filter out superfluous whitespace between tags.

QString xmlIn = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\" ?>"
                "<Analyser><JointDetails>              <Details><StdThickness>"
                " T </StdThickness><Thickness_num> 0.032 </Thickness_num>"
                "</Details>   </JointDetails></Analyser>";
QString xmlOut;

QXmlStreamReader reader(xmlIn);
QXmlStreamWriter writer(&xmlOut);
writer.setAutoFormatting(true);

while (!reader.atEnd()) {
    reader.readNext();
    if (!reader.isWhitespace()) {
        writer.writeCurrentToken(reader);
    }
}

qDebug() << xmlOut;

Answer 2

If you're using Qt, you can read it with QXmlStreamReader and write it with QXmlStreamWriter, or parse it as QDomDocument and convert that back to QString. Both QXmlStreamWriter and QDomDocument support formatting.