Using html5 instead of nsxmlparser to parse an xml file

I used to have nsxmlparser that downloads and parses an xml file into table of rows (each row has the article's headline+summary) If I click on the headline then it shows the view of the complete article. Now I m learning html5 and d like to achieve the same effect. Th开发者_Go百科is view should work both online and offline. How do I get started?