Writing Subchild with DOM

Aashu10

I already have an XML file, I need to write under a Header, Below i have show a my XML file.

<MAIN_HEADER>
  
  <HEADER1>
  //it's child
  </HEADER1>

  <HEADER2>
  //it's child>
  </HEADER2>

  <HEADER3>
  //EMPTY
  </HEADER3>
  
  <HEADER4>
  //it's child
  </HEADER4>

</MAIN_HEADER>

I need to write child and subchild inside HEADER3 . Below is my code.

QFile file(output);
    if(!file.open(QIODevice::ReadOnly | QIODevice::Text))
    {
        qDebug()<<"file doesnt exists";
    }
    QDomDocument domDocument;
    if( !domDocument.setContent( &file ) )
    {
        qDebug()<<"Error";

        return;
    }

    QDomElement topElement = domDocument.documentElement();
    QDomNode domNode = topElement.firstChild();
    while(!domNode.isNull())
    {
                    QDomElement domElement = domNode.toElement();
                    if(!domElement.isNull())
                    {

        if(domElement.tagName() == "HEADER3")
        {
            for(int i=0; i<List.count();i++)
            {
                QDomElement node = domDocument.createElement("CHILD");
                node.setAttribute("Name", List[i].Filename);
                node.setAttribute("Value", List[i].value);
                domElement.appendChild(node);
                if(List[i].subChild.size() != 0)
                {
                    QDomElement subNode =   domDocument.createElement("SubChild");
                    subNode.setAttribute("Name", List[i].SubChild);
                    node.appendChild(subNode);
                }
            }
        }


                }
domNode = domNode.nextSibling();
            }
    file.close();

    QFile outfile( output);
    if( !outfile.open( QIODevice::WriteOnly | QIODevice::Text ) )
    {
        qDebug()<<"Error";
    }

    QTextStream stream1( &outfile );
    stream1 << dom.toString();
    outfile.close();

This code gets stuck inside while loop, I'm not so sure about the hierarchy in this code. I just want to write the contents in <HEADER3>

JohanSolo

@Aashu10 said:

My code get's stuck when i compile it. I am very new to DOM Parser.

Please elaborate what you mean? Getting stuck when compiling? What is the error?

Aashu10

No error, It's just stuck, When i debuged it. I found it's stuck in the while loop.

JohanSolo

@Aashu10 said:

No error, It's just stuck, When i debuged it. I found it's stuck in the while loop.

OK, so the code compiles.

I think you never go to the next node... it just reads forever and ever the first node of you document.

Aashu10

Any suggestion how to bypass this?

JohanSolo

Well, at some point you must read you document, i.e. go from one node to the other. At the end of the loop you should do something like domNode = domeNode.nextSibling(). If you don't do so, you're endlessly reading the first node of your document, as I've told you before.

Aashu10

Ah! Thank you! @JohanSolo Now it goes through the loop properly, but the contents of the header is still empty. I just debugged, found out it never goes into

if(domElement.text() == "HEADER3")

I am not sure about hierarchy in the code. but the hierarchy in my XML file is as shown in this XML file

@JohanSolo I have edited the code accordingly

JohanSolo

@Aashu10 said:

if(domElement.text() == "HEADER3")
I am not sure about hierarchy in the code. but the hierarchy in my XML file is as shown in this XML file

Use tagName(), text() returns the text contained in a tag.

Aashu10

Yes! @JohanSolo Now it goes inside the loop, but does not write the contents inside HEADER3. This time i have no idea why. I have updated the code. Please do take a look.

JohanSolo

I don't see any obvious mistake. Note that I've never used QDomDocument to write a file. It's such a waste of memory according to me...

Edit: you should get a look at the returned value of appendChild to check that everything went fine.

Aashu10

Thanks for replying, How do i check the return value of that. Sorry not so proficient with DomDocument.

JohanSolo

@Aashu10 said:

Thanks for replying, How do i check the return value of that. Sorry not so proficient with DomDocument.

Have a look at the doc