iOS json生成与解析

1.  json生成

bool sendCmd(int msg_id,NSString* type,NSString* param)
{
    NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:[NSNumber numberWithInt:mSession], @"token", [NSNumber numberWithInt:msg_id], @"msg_id", nil, nil];//不可变字典

    NSMutableDictionary *mutableDic = [NSMutableDictionary dictionaryWithDictionary:dic];//可变字典
    if(type!=nil) [mutableDic setObject:type forKey:@"type"];
    if(param!=nil) [mutableDic setObject:param forKey:@"param"];

    NSError *parseError = nil;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:mutableDic options:NSJSONWritingPrettyPrinted error:&parseError];

    NSString *szCmd = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
    szCmd = [szCmd stringByReplacingOccurrencesOfString:@" " withString:@""];//去掉空格
    szCmd = [szCmd stringByReplacingOccurrencesOfString:@"\r" withString:@""];//去掉回车
    szCmd = [szCmd stringByReplacingOccurrencesOfString:@"\n" withString:@""];//去掉换行
    NSLog(@"%@",szCmd);
    return sendData(szCmd);
}

2. json解析

bool OnReceive(uint8_t* buf, long len)
{
    NSData *json = [NSData dataWithBytes:buf length:len];
    NSMutableData *jsonData = [[NSMutableData alloc] init];
    [jsonData appendData:json];
    NSString *szjson = [[NSString alloc] initWithData:json encoding:NSUTF8StringEncoding];
    NSLog(@"%@", szjson);

    NSError *error = nil;
    NSDictionary *jsonDic = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableLeaves error:&error];

    NSNumber *msg_id = [jsonDic objectForKey:@"msg_id"];
    switch([msg_id intValue]) {
        case 257: {
            NSNumber *session = [jsonDic objectForKey:@"param"];
            int mSession = [session intValue];
        }
            break;

        default:
            break;
    }
    return true;
}