1.ios解析json 
使用開源json包，項目地址： 
     http://stig.github.com/json-framework/ 
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解析對象 
[parser release]; 
     //發(fā)送者 
     NSString * sender = [dicMessageInfo objectForKey:@"sender"]; 

2.json嵌套對象解析： 
//要上傳的字符串 
    NSString *dataStr=[[NSString alloc] initWithString:@"{/"cross/":{/"1/":/"true/",/"2/":/"false/",/"3/":/"true/"}}"]; 
//獲取響應返回字符串 
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解析對象 
            
            NSMutableDictionary * cross = [dicMessageInfo objectForKey:@"cross"]; 
            
            NSString *cross1= [cross objectForKey:@"1"]; 
            //解析json到各個字符串 
            //發(fā)送者 
            [parser release]; 
            NSLog(@"cross1: %@",cross1); 
3.拼接json字符串 

通過使用SBJson中的SBJsonWriter類的方法- (NSString*)stringWithObject:(id)value可以將一個對象中的值格式化為json字符串，符合key/value格式的數據封裝到NSDictionary后可以使用該方法進行格式化，其他數據通過拼接字符串的方式格式化。 
在拼接過程中可以使用類NSMutableString的方法： 
- (void)appendString:(NSString *)aString;、 
- (void)appendFormat:(NSString *)format, ... NS_FORMAT_FUNCTION(1,2); 
動態(tài)添加字符串。 
拼接的字符串可通過json在線驗證的方式驗證其格式是否正確，網址為： 
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.利用多個NSDictionary，拼接多層嵌套的json字符串，減少因手工拼接忘記加引號導致的json格式錯誤 
示例代碼： 
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); 
5.json字符串在線校驗網址： 
http://jsonlint.com/