JSON JavaScript Object Notation，轻量级数据交换格式。

一、文档结构

• 特点：无序的，“名称-值”对集合。
• 格式：对象{"名称1":"值1:","名称2":"值2",.....}
  数组有序集合["值1","值1",......]

二、数据编码/解码

• SBJson 比较老的框架，更新频繁，支持ARC
• TouchJSON 比较老，支持ARC和MRC
• YAJL 比较优秀的JSON框架，基于SBJson优化，但不支持ARC
• **NextiveJson 非常优秀的JSON框架，与JSONKit性能相似，不支持ARC
• NSJSONSerialization iOS 5之后苹果提供的API，很优秀且快速，占用内存小，支持ARC，推荐使用

三、应用

3.1 NSJSONSerialization解码

NSError *jsonError;
NSDictionary *dataDic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&jsonError];
if (!jsonError || jsonError){
          NSLog(@"解析失败！");
}else{
          NSLog(@"解析成功！");
}

3.1 NSJSONSerialization编码

- (void)registerWithInfoDic:(NSDictionary *)infoDic complet:(void (^)(NSDictionary *netObject, BOOL isSeccuss))complete{
    
    NSString *parameterStr = [[NSString alloc] initWithFormat:@"?localIp=%@&localPort=%@&userId=%@&userPwd=%@", [infoDic objectForKey:@"localIp"]
                      , [infoDic objectForKey:@"localPort"]
                      , [infoDic objectForKey:@"userId"]
                      , [infoDic objectForKey:@"userPwd"]
                              ];
    NSString *strUrl = [NSString stringWithFormat:@"http://192.168.0.45:8080/webDemo/Register%@",parameterStr];
    
    strUrl = [strUrl stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];
    
    NSURL *url = [NSURL URLWithString:strUrl];
    
    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
    NSURLSession *session = [NSURLSession sharedSession];
    
    NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *taskError){
        NSLog(@"Register请求完成！");
        if (!taskError) {
            //NSError *jsonError = nil;
          NSDictionary *dataDic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:nil];
            complete(dataDic,YES);
        }else{
            NSLog(@"\ntask error: %@", taskError.localizedDescription);
            complete(nil,NO);
        }
    }];
    
    [task resume];
}

   NSDictionary *dic = @{@"localIp":@"192.168.0.1",@"localPort":@"12345",@"userId":@"12345",@"userPwd":@"123456"};
    //NSLog(@"测试按钮点击");
    [[WebConnect sharedWebConnect] registerWithInfoDic:dic complet:^(NSDictionary *netObject, BOOL isSeccuss){
        if (isSeccuss) {
            NSLog(@"netObject: %@",netObject);
        }
    }];