<?xml version="1.0" encoding="utf-8" ?>
<root>
    <systemConfig>
      <CityName>北京</CityName>
      <CityCode>201</CityCode>
      <ParentCityCode> 0</ParentCityCode>
      <areaCode>010</areaCode>
      <AgreementUrl></AgreementUrl>
      <IntentionLevel>                       
        <Item key="1" value="A"></Item>
        <Item key="2" value="B"></Item>
        <Item key="3" value="C"></Item>
      </IntentionLevel>
      <ComeChannel>                           
        <Item key="1" value="报纸"></Item>
        <Item key="2" value="杂志"></Item>
      </ComeChannel>
      <BuyCarBudget>                       
        <Item key="1" value="40-50万"></Item>
        <Item key="2" value="50-60万"></Item>
      </BuyCarBudget>
     <IntentionColor>
         <Item key="1" value="红"></Item>
         <Item key="2" value="黄"></Item>
     </IntentionColor>
    </systemConfig>
</root>

    //(1)添加头文件搜索路径
    //      Header Search Paths-> /usr/include/libxml2
    //(2)添加二进制库
    //  Link library ->  lixml2.dylib
    //(3)源文件添加编译选项
    //      -fno-objc-arc
    //(4)添加头文件
    //  #import "GDataXMLNode.h"

 //1.加载和解析XML文件
    NSString *path = [[NSBundle mainBundle] pathForResource:@"xml.txt" ofType:nil];
    NSData *data = [[NSData alloc] initWithContentsOfFile:path];
    //GDataXMLDocument 表示XML文档对象
    //initWithData  使用NSData初始化，就是解析
    GDataXMLDocument *doc = [[GDataXMLDocument alloc] initWithData:data options:0 error:nil];
    
    //2.获取指令语法  XPath
    //CityName路径: /root/systemConfig/CityName
    
    NSArray *array = [doc nodesForXPath:@"/root/systemConfig/CityName" error:nil];
    GDataXMLElement *element = [array firstObject];
    NSLog(@"name = %@ value = %@",element.name,element.stringValue);
    
    //获取指定节点的属性
    NSArray *items = [doc nodesForXPath:@"/root/systemConfig/ComeChannel/Item"  error:nil];
    GDataXMLElement *item = [items firstObject];
    //取属性,属性使用GDataXMLElement表示
    for(GDataXMLElement *attr in item.attributes)
    {
        NSLog(@"name = %@ value = %@",attr.name,attr.stringValue);
    }
    
    //4.获取所有指定名字的节点，不管位置
    //XPath语法：//Item
    
    NSArray *allItem = [doc nodesForXPath:@"//Item" error:nil];
    for(GDataXMLElement *e in allItem)
    {
        NSLog(@"name = %@",e.name);
    }
    
    //5.获取所有指定名字的属性，不管位置
    //XPath语法： //@value
    NSArray *allValue = [doc nodesForXPath:@"//@value" error:nil];
    for(GDataXMLElement *e in allValue)
    {
        NSLog(@"value = %@",e.stringValue);
    }
    
    //6.逐层遍历XML文件
    //获取根节点
    //GDataXMLElement *root = doc.rootElement ;
    //获取子节点
    //root.children
    //获取子节点个数
    //root.childrenCount
    //获取指定名字的子节点
    //root elementsForName