如何获取iPhone资源文件夹中的文件夹和文件列表？

我在我的资源文件夹中做文件夹结构,如… resource => MyData => S1
然后在S1 => Name.png,data.ppt

现在我想获取所有文件夹列表和文件名.这里MyData名称只是静态其他可能会改变.就像我可以添加S1,S2,S3和文件数量.那么如何通过Objective C阅读这些内容呢？我试过下面的代码.

NSString *bundlePathName = [[NSBundle mainBundle] bundlePath];
    NSString *dataPathName = [bundlePathName StringByAppendingPathComponent:@"resources"];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    if ([fileManager fileExistsAtPath:dataPathName]) {
        NSLog(@"%@ exists",dataPathName);
        BOOL isDir = NO;
        [fileManager fileExistsAtPath:dataPathName isDirectory:(&isDir)];
        if (isDir == YES) {
            NSLog(@"%@ is a directory",dataPathName);
            NSArray *contents;
            contents = [fileManager contentsOfDirectoryAtPath:dataPathName error:nil];
            for (NSString *entity in contents) {
                NSLog(@"%@ is within",entity);
            }
        } else {
            NSLog(@"%@ is not a directory",dataPathName);
        }
    } else {
        NSLog(@"%@ does not exist",dataPathName);
    }

谢谢,

NSString * resourcePath = [[NSBundle mainBundle] resourcePath];

NSString * documentsPath = [resourcePath StringByAppendingPathComponent:@"Documents"];

NSError * error;
NSArray * directoryContents = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:documentsPath error:&error];