Swift

在做一些应用的时候经常需要用到XML解析，比如获取Web Service数据，读取RSS新闻或者博客数据源。下面演示了两个非常方便高效的XML库在Swift里的调用方法。

假设需要被解析的XML数据文件users.xml如下：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

<?xml version="1.0" encoding="utf-8"?>  <Users>      <User id="101">         <name>航歌</name>         <tel>             <mobile>1234567</mobile>             <home>025-8100000</home>         </tel>      </User>      <User id="102">         <name>hangge</name>         <tel>             <mobile>8989889</mobile>             <home>025-8122222</home>         </tel>     </User>  </Users>

我们需要实现的功能是解析并打印出需要的数据：

1 2	User: uid:101,uname:航歌,mobile:1234567,home:025-8100000 User: uid:102,uname:hangge,mobile:8989889,home:025-8122222

一，使用GDataXML（这个是google出品的） 

1，在build phases -> Link Binary With Libraries中，点击“+”添加“libxml2.2.dylib”

 

2，在build setting -> Header Search Paths里添加 ${SDK_DIR}/usr/include/libxml2

 

3，在build setting里的Objective-C编译选项里，把自动引用计数改为No，否则在应用GDataXML库时会编译有错

 

4，添加bridge.h头文件并设置到编译参数里

1	#import "GDataXMLNode.h"

5，导入GDataXML库文件（GDataXMLNode.h和GDataXMLNode.m），代码结构如下：

 

6，开始解析（ViewController.swift）

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54

import UIKit   class ViewController: UIViewController {                                   override func viewDidLoad() {         super.viewDidLoad()         // Do any additional setup after loading the view, typically from a nib.         var label:UILabel = UILabel(frame:CGRectMake(100, 100,300,100));         label.text = "输出结果在控制台"         self.view.addSubview(label)         //测试Swift调用Object的XML库功能         testXML()     }           override func didReceiveMemoryWarning() {         super.didReceiveMemoryWarning()         // Dispose of any resources that can be recreated.     }       func testXML() {         //获取xml文件路径         var path = NSBundle.mainBundle().pathForResource("users", ofType:"xml")         //获取xml文件内容         var xmlData = NSData(contentsOfFile:path!)         //可以转换为字符串输出查看         //println(NSString(data:xmlData, encoding:NSUTF8StringEncoding))                   //使用NSData对象初始化文档对象         //这里的语法已经把OC的初始化函数直接转换过来了         var doc:GDataXMLDocument = GDataXMLDocument(data:xmlData, options : 0, error : nil)                   //获取Users节点下的所有User节点，显式转换为element类型编译器就不会警告了         //var users = doc.rootElement().elementsForName("User") as GDataXMLElement[]                   //通过XPath方式获取Users节点下的所有User节点，在路径复杂时特别方便         var users = doc.nodesForXPath("//User", error:nil) as [GDataXMLElement]                   for user in users {             //User节点的id属性             let uid = user.attributeForName("id").stringValue()             //获取name节点元素             let nameElement = user.elementsForName("name")[0] as GDataXMLElement             //获取元素的值             let uname =  nameElement.stringValue()             //获取tel子节点             let telElement = user.elementsForName("tel")[0] as GDataXMLElement             //获取tel节点下mobile和home节点             let mobile = (telElement.elementsForName("mobile")[0] as GDataXMLElement).stringValue()             let home = (telElement.elementsForName("home")[0] as GDataXMLElement).stringValue()             //输出调试信息             println("User: uid:(uid),uname:(uname),mobile:(mobile),home:(home)")         }           } }

示例下载：GDataXML.zip

二，使用DDXML

1，2，3步同上

4，添加bridge.h头文件并设置到编译参数里

1 2	#import "DDXML.h" #import "DDXMLElementAdditions.h"

5，导入DDXML库文件

6，开始解析（ViewController.swift）

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

import UIKit   class ViewController: UIViewController {           override func viewDidLoad() {         super.viewDidLoad()         // Do any additional setup after loading the view, typically from a nib.         var label:UILabel = UILabel(frame:CGRectMake(100, 100,300,100));         label.text = "输出结果在控制台"         self.view.addSubview(label)         //测试Swift调用Object的XML库功能         testXML()     }           override func didReceiveMemoryWarning() {         super.didReceiveMemoryWarning()         // Dispose of any resources that can be recreated.     }           func testXML() {         //获取xml文件路径         var path = NSBundle.mainBundle().pathForResource("users", ofType:"xml")         //获取xml文件内容         var xmlData = NSData(contentsOfFile:path!)                   //构造XML文档         var doc = DDXMLDocument(data: xmlData, options:0, error:nil)                   //利用XPath来定位节点（XPath是XML语言中的定位语法，类似于数据库中的SQL功能）         var users = doc.nodesForXPath("//User", error:nil) as [DDXMLElement]         for user in users {             let uid = user.attributeForName("id").stringValue()             //DDXMLElementAdditions提供了elementForName获取单个节点，不用获取数组了             let uname = user.elementForName("name").stringValue()             //获取tel节点的子节点             let telElement = user.elementForName("tel") as DDXMLElement             let mobile = (telElement.elementForName("mobile") as DDXMLElement).stringValue()             let home = (telElement.elementForName("home") as DDXMLElement).stringValue()             println("User: uid:(uid),uname:(uname),mobile:(mobile),home:(home)")         }            } }

示例下载：DDXML.zip