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ios的Objective-C如何解析XML,你是这样做的吗

本文以解析本地XML为例,网络获取到的返回值只需转换成NSData型,解析是同理

需要解析的xml文件如下,users.xml

<?xml version="1.0" encoding="utf-8"?>
<AllUsers>
<message>用户信息</message>
<user>
<name>第一个用户名</name>
<age>10</age>
<school>JiangSu University</school>
</user>
<user>
<name>第二个用户名</name>
<age>22</age>
<school>NanJing University</school>
</user>
<user>
<name>第三个用户名</name>
<age>23</age>
<school>HongKong University</school>
</user>
</AllUsers>

我们用一个数组来存放,最终数据结构为

(
{
message = "用户信息";
},
{
age = 10;
name = "第一个用户名";
school = "JiangSu University";
},
{
age = 22;
name = "第二个用户名";
school = "NanJing University";
},
{
age = 23;
name = "第三个用户名";
school = "HongKong University";
}
)

解析步骤

一、声明代理 NSXMLParserDelegate

二、解析

// 遇到节点message和user时作为一个字典存放
NSArray *keyElements = [[NSArray alloc] initWithObjects:@"message",@"user", nil];
// 需要解析的字段
NSArray *rootElements = [[NSArray alloc] initWithObjects:@"message",@"name",@"age",@"school", nil];
// 获取xml文件的路径
NSString *xmlPath = [[NSBundle mainBundle] pathForResource:@"users" ofType:@"xml"];
// 转化为Data
NSData *data = [[NSData alloc] initWithContentsOfFile:xmlPath];
 
// 初始化
NSXMLParser *xmlParser = [[NSXMLParser alloc] initWithData:data];
 
// 代理
xmlParser.delegate = self;
// 开始解析
BOOL flag = [xmlParser parse];
if (flag) {
NSLog(@"解析成功");
}
else{
NSLog(@"解析出错");
}

中间变量,在.m的interface的中定义

NSString *currentElement;
NSString *currentValue;
NSMutableDictionary *rootDic;
NSMutableArray *finalArray;

代理方法

#pragma - mark 开始解析时
-(void)parserDidStartDocument:(NSXMLParser *)parser
{
// 用数组存储每一组信息
finalArray = [[NSMutableArray alloc] init];
 
}
#pragma - mark 发现节点时
-(void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
for(NSString *key in self.keyElements){
if ([elementName isEqualToString:key]) {
// 关键节点开始时,初始化一个字典来存放值
rootDic = nil;
 
rootDic = [[NSMutableDictionary alloc] initWithCapacity:0];

}
else {
for(NSString *element in self.rootElements){
if ([element isEqualToString:element]) {
currentElement = elementName;
currentValue = [NSString string];
}
}
}
}
}
#pragma - mark 发现节点值时

-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{

if (currentElement) {

currentValue = string;
[rootDic setObject:string forKey:currentElement];
}

}
#pragma - mark 结束节点时
-(void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if (currentElement) {
[rootDic setObject:currentValue forKey:currentElement];
currentElement = nil;
currentValue = nil;
}
for(NSString *key in self.keyElements){

if ([elementName isEqualToString:key]) {
// 关键节点结束时,将字典存放在数组中
if (rootDic) {

[finalArray addObject:rootDic];
}
}
}
}
#pragma - mark 结束解析
-(void)parserDidEndDocument:(NSXMLParser *)parser
{
}

最后解析完成后,打印出finalArray为

{
message = "\U7528\U6237\U4fe1\U606f";
},
{
age = 10;
name = "\U82b3\U4ed4\U5c0f\U811a\U5370";
school = "JiangSu University";
},
{
age = 22;
name = "\U6bd2\U866b";
school = "NanJing University";
},
{
age = 23;
name = "\U5973\U795e";
school = "HongKong University";
}
)