XML- Explanation

[Paawan]

Good Day,

I want to understand the following methods in XML handlers:

startDocument(): How does this method work? Does it look for the first "<" element or any text?

endDocument(): How does it know the document has ended?

startElement(): Again how does it know the element has started

endElement(): How does it know it is the end element?

Thanks

[JKSH]

Hi,

I haven't used the handlers you posted, but here is what I know about QXmlStreamReader. I believe the detection mechanism is similar:

All tokens are detected when the '>' character is found.

• StartDocument is detected at the '>' of the XML declaraion.
• StartElement is detected at the '>' of an element start tag.
• EndElement is detected at the '>' of an element end tag.
• EndDocument is detected at the '>' of the end tag of your top-level element.

Using the following document as an example:
@
<?xml version="1.0" encoding="UTF-8"?>
<Reply category="INIT">
<InitClusters>
<Cluster id="A" x="0" y="0"/>
<Cluster id="B" x="2" y="2"/>
</InitClusters>
</Reply>
@

• <?xml version="1.0" encoding="UTF-8"?> -- StartDocument
• <Reply category="INIT"> -- StartElement
• <InitClusters> -- StartElement
• <Cluster id="A" x="0" y="0"/> -- StartElement and EndElement
• <Cluster id="B" x="2" y="2"/> -- StartElement and EndElement
• </InitClusters> -- EndElement
• </Reply> -- EndElement and EndDocument

[Paawan]

Thanks for the reply.

Can we say that <something> is a start element ?

and

</something> is an end element?

Is my understanding correct?

The reader/handler knows it has reached the end of the document because it has previous read <Reply category="INIT"> and then it has found the </Reply> element.

Is my understanding correct?

Thank you for the help.

[JKSH]

You're welcome.

[quote author="Paawan" date="1410075609"]Can we say that <something> is a start element ?

and

</something> is an end element?

Is my understanding correct?[/quote]Correct.

Also, <something/> is a small element that starts and ends at the same time.

[quote author="Paawan" date="1410075609"]The reader/handler knows it has reached the end of the document because it has previous read <Reply category="INIT"> and then it has found the </Reply> element.

Is my understanding correct?[/quote]Correct.

[Paawan]

Thank you very much again.

[Paawan]

There has been a sample XML file that was given with the book.

@
<section id="xmlintro">
<title> Intro to XML </title>
<p> This is a paragraph </p>
<ul>
<li> This is an unordered list item. </li>
<li c="textbook"> This only shows up in the textbook </li>
</ul>

<p> The code example below shows how
     slacker processes includes: </p>
<include src="testhello.cpp" mode="cpp"/>

<p> And here is another paragraph </p>
</section>

@

In this file the xml version part is not given. How will the reader know that document is starting? By this I mean where is the StartDocument part in this file?

Thanks