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I just implemented my first XmlParser object (MyParserObj) that relies on the NSXMLParser object. This parser is embedded inside a tableviewController (MyTableViewController) and it starts parsing at MyTableViewController's viewDidLoad method.

Ok.This is working just fine.It's a small Xml file though! I was wondering if I should choose a different approach when dealing with big Xml files? Will memory suffer when parsing large xml documents?

UPDATE

The real point I want to understand is the flow of the process:

I placed few breakpoints now and it looks like this:

  • the app first encounters ( inside MyTableViewController's viewDidLoad method )the [MyParserObj parseXMLFileAtURL:path] and starts parsing the Xml document;
  • The app finishes parsing the whole Xml Document (parserDidEndDocument..);
  • The tableviewController starts populating its tableView Cells (cellForRowAtIndexPath..);

Apart from choosing a XmlParser (Between those you suggested) that is more or less time/memory consuming are the above steps going to be the same?

If positive, is it correct to think of starting populating the cells as soon as The Parser is done with that specific element?How do I do that?

thanks

Luca

luca
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3 Answers3

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Jim Dovey create a nice blog post about parsing big XML files.

http://blog.alanquatermain.me/2009/04/06/aqxmlparser-equals-equals-big-memory-win/ here Jim describes his one XML parser wich user les memory then other parser.

So if you need to parse large XML files I would suggest you have a look het the open source XML parser AQXMLParser which is the parser create in the blog post.

Jim Dovey
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rckoenes
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On iPhone devices, you don't have the NSXMLDocument available on MAC which reads the whole XML document into memory. There are many XML Parser classes available, and you can find them in the link below.

http://www.raywenderlich.com/553/how-to-chose-the-best-xml-parser-for-your-iphone-project

This tutorial on Ray Wenderlich is what u need to read to know which xml reader is best for your app.

For my own applications, I use SMXMLDocument, you can read about it here: http://nfarina.com/post/2843708636/a-lightweight-xml-parser-for-ios

Ramy Kfoury
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for big data, i suggest u json instead of xml, see here a tutorial

http://www.readwriteweb.com/hack/2010/11/json-vs-xml.php

Saad
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  • I agree to this that for huge data to be received over the server it will be better to use JSON rather than using the XML as its a lightweight object and renders faster than XML – Akhilesh Sharma May 21 '12 at 09:25