简介Objective-C解析XML与JSON数据格式的方法
程序员文章站
2022-07-11 18:16:21
解析xml
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
// 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
{
}
解析完成后，打印出finalarray为
nsdata * responsedata = [respones responsedata];
nsstring * strresponser = [[nsstring alloc] initwithdata:responsedata encoding:nsutf8stringencoding];
sbjsonparser * parser = [[sbjsonparser alloc]init];
nsmutabledictionary *dicmessageinfo = [parser objectwithstring:strresponser]; // 解析成json解析对象
[parser release];
//发送者
nsstring * sender = [dicmessageinfo objectforkey:@"sender"];
2.json嵌套对象解析：
//要上传的字符串
nsstring *datastr=[[nsstring alloc] initwithstring:@"{\"cross\":{\"1\":\"true\",\"2\":\"false\",\"3\":\"true\"}}"];
//获取响应返回字符串
nsdata * responsedata = [respones responsedata];
nsstring * strresponser = [[nsstring alloc] initwithdata:responsedata encoding:nsutf8stringencoding];
//嵌套解析
sbjsonparser * parser = [[sbjsonparser alloc]init];
nsmutabledictionary *dicmessageinfo = [parser objectwithstring:strresponser]; // 解析成json解析对象
nsmutabledictionary * cross = [dicmessageinfo objectforkey:@"cross"];
nsstring *cross1= [cross objectforkey:@"1"];
//解析json到各个字符串
//发送者
[parser release];
nslog(@"cross1: %@",cross1);
3.拼接json字符串
- (void)appendstring:(nsstring *)astring;、
- (void)appendformat:(nsstring *)format, ... ns_format_function(1,2);
动态添加字符串。
拼接的字符串可通过json在线验证的方式验证其格式是否正确，网址为：
http://jsonlint.com/
-(nsstring *) getjsonstring
{
nsmutablestring *json = [nsmutablestring stringwithcapacity:128];
nsstring *jsonstring=nil;
sbjsonwriter *writer = [[sbjsonwriter alloc] init];
[json appendstring:@"{\"data\":{"];
[json appendformat:@"\"%@\":\"%d\",",@"reset",reset];
if(missionstatus!=null)
{
jsonstring=[writer stringwithobject:status];
if(jsonstring!=null)
{
[json appendstring:@"\"status\":"];
[json appendstring:jsonstring];
}
}
[json appendstring:@"}}"];
return json;
}
4.利用多个nsdictionary，拼接多层嵌套的json字符串，减少因手工拼接忘记加引号导致的json格式错误
示例代码：
nsdictionary *datadictionary= [nsdictionary dictionarywithobjectsandkeys:mac,@"mac",
game,@"game",
devicetoken,@"devicetoken",
device,@"device",
gv,@"gv",
lang,@"lang",
os,@"os",
hardware,@"hardware",
down,@"down",nil];
nsdictionary *parmdictionary= [nsdictionary dictionarywithobjectsandkeys:@"getsession",@"act",
datadictionary,@"data",nil];
nsdictionary *jsondictionary=[nsdictionary dictionarywithobjectsandkeys:pv,@"pv",
parmdictionary,@"param",nil];
sbjsonwriter *writer = [[sbjsonwriter alloc] init];
nsstring *jsonstring=nil;
jsonstring=[writer stringwithobject:jsondictionary];
nslog(@"%@",jsonstring);
解析xml
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>芳仔小脚印</name> <age>10</age> <school>jiangsu university</school> </user> <user> <name>毒虫</name> <age>22</age> <school>nanjing university</school> </user> <user> <name>女神</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 = "芳仔小脚印";
school = "jiangsu university";
},
{
age = 22;
name = "毒虫";
school = "nanjing university";
},
{
age = 23;
name = "女神";
school = "hongkong university";
}
)
解析步骤
一、声明代理 nsxmlparserdelegate
二、解析
复制代码 代码如下:
// 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
复制代码 代码如下:
nsstring *currentelement;
nsstring *currentvalue;
nsmutabledictionary *rootdic;
nsmutablearray *finalarray;
代理方法
复制代码 代码如下:
#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
{
}
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";
}
)
使用sbjson拼接和解析json
1.ios解析json
使用开源json包，项目地址：
http://www.superloopy.io/json-framework/
复制代码 代码如下:
nsdata * responsedata = [respones responsedata];
nsstring * strresponser = [[nsstring alloc] initwithdata:responsedata encoding:nsutf8stringencoding];
sbjsonparser * parser = [[sbjsonparser alloc]init];
nsmutabledictionary *dicmessageinfo = [parser objectwithstring:strresponser]; // 解析成json解析对象
[parser release];
//发送者
nsstring * sender = [dicmessageinfo objectforkey:@"sender"];
2.json嵌套对象解析：
复制代码 代码如下:
//要上传的字符串
nsstring *datastr=[[nsstring alloc] initwithstring:@"{\"cross\":{\"1\":\"true\",\"2\":\"false\",\"3\":\"true\"}}"];
//获取响应返回字符串
nsdata * responsedata = [respones responsedata];
nsstring * strresponser = [[nsstring alloc] initwithdata:responsedata encoding:nsutf8stringencoding];
//嵌套解析
sbjsonparser * parser = [[sbjsonparser alloc]init];
nsmutabledictionary *dicmessageinfo = [parser objectwithstring:strresponser]; // 解析成json解析对象
nsmutabledictionary * cross = [dicmessageinfo objectforkey:@"cross"];
nsstring *cross1= [cross objectforkey:@"1"];
//解析json到各个字符串
//发送者
[parser release];
nslog(@"cross1: %@",cross1);
3.拼接json字符串
通过使用sbjson中的sbjsonwriter类的方法- (nsstring*)stringwithobject:(id)value可以将一个对象中的值格式化为json字符串，符合key/value格式的数据封装到nsdictionary后可以使用该方法进行格式化，其他数据通过拼接字符串的方式格式化。
在拼接过程中可以使用类nsmutablestring的方法：
复制代码 代码如下:
- (void)appendstring:(nsstring *)astring;、
- (void)appendformat:(nsstring *)format, ... ns_format_function(1,2);
动态添加字符串。
拼接的字符串可通过json在线验证的方式验证其格式是否正确，网址为：
http://jsonlint.com/
复制代码 代码如下:
-(nsstring *) getjsonstring
{
nsmutablestring *json = [nsmutablestring stringwithcapacity:128];
nsstring *jsonstring=nil;
sbjsonwriter *writer = [[sbjsonwriter alloc] init];
[json appendstring:@"{\"data\":{"];
[json appendformat:@"\"%@\":\"%d\",",@"reset",reset];
if(missionstatus!=null)
{
jsonstring=[writer stringwithobject:status];
if(jsonstring!=null)
{
[json appendstring:@"\"status\":"];
[json appendstring:jsonstring];
}
}
[json appendstring:@"}}"];
return json;
}
4.利用多个nsdictionary，拼接多层嵌套的json字符串，减少因手工拼接忘记加引号导致的json格式错误
示例代码：
复制代码 代码如下:
nsdictionary *datadictionary= [nsdictionary dictionarywithobjectsandkeys:mac,@"mac",
game,@"game",
devicetoken,@"devicetoken",
device,@"device",
gv,@"gv",
lang,@"lang",
os,@"os",
hardware,@"hardware",
down,@"down",nil];
nsdictionary *parmdictionary= [nsdictionary dictionarywithobjectsandkeys:@"getsession",@"act",
datadictionary,@"data",nil];
nsdictionary *jsondictionary=[nsdictionary dictionarywithobjectsandkeys:pv,@"pv",
parmdictionary,@"param",nil];
sbjsonwriter *writer = [[sbjsonwriter alloc] init];
nsstring *jsonstring=nil;
jsonstring=[writer stringwithobject:jsondictionary];
nslog(@"%@",jsonstring);