Cocoa Programming for OS X: The Big Nerd Ranch Guide

For the More Curious: Parsing XML

There are two standard approaches to parsing XML. The high-level method (DOM parsing) is to use NSXMLDocument and NSXMLNode. If you have an NSData object containing the following XML:

<​?​x​m​l​ ​v​e​r​s​i​o​n​=​"​1​.​0​"​ ​e​n​c​o​d​i​n​g​=​"​U​T​F​-​8​"​?​>​
<​p​e​o​p​l​e​>​
 ​ ​<​p​e​r​s​o​n​>​
 ​ ​ ​ ​<​f​i​r​s​t​>​P​a​t​r​i​c​k​<​/​f​i​r​s​t​>​
 ​ ​ ​ ​<​l​a​s​t​>​R​o​b​i​n​s​o​n​<​/​l​a​s​t​>​
 ​ ​<​/​p​e​r​s​o​n​>​
<​/​p​e​o​p​l​e​>​

NSXMLDocument will parse it into a handy tree (Figure 28.7):

Figure 28.7  Parsed XML document

You can then traverse the tree manually or use XPath queries ...