向后台发送json数据

//将字典转为json格式的数据

// NSJSONWritingPrettyPrinted 转化的json数据有换位符 /n

NSData *jsonData = [NSJSONSerialization dataWithJSONObject:_dataDic options:0 error:nil];

NSMutableData *data = [NSMutableData dataWithData:jsonData];

NSString *JsonStr = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];

NSInteger uid = [USERUID intValue];

params[@"uid"] = @(uid);

params[@"utoken"] = USERUTOKEN;

params[@"driver"] = JsonStr ;