IOS自带json解析类解析json

- (IBAction)test:(id)sender {
    NSString *result = @"{"code":"S00000","message":"success","data":{"file_name":"b1feba4439d0bed9f867123637121b24-dc7764fb24f7294c6a3dcb6971eddb25.png","paths":["x1","x2","x3","x5","x6","x7","x8","xm"]}}";
    NSError *error;
    NSData* response = [result dataUsingEncoding:NSUTF8StringEncoding];

    NSDictionary *jsonInfo = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableContainers error:&error];
    NSString *code = [jsonInfo objectForKey:@"code"];
    
    NSLog([NSString stringWithFormat:@"%@",code]);
    
    NSDictionary *data = [jsonInfo objectForKey:@"data"];
    NSLog([NSString stringWithFormat:@"%@",[data objectForKey:@"file_name"]]);
}

第6行的NSJSONReadingOption是干嘛的没搞明白 用NSJSONReadingMutableLeaves也能正常解析