ios - 知道对象是否为文件夹的资源占用最少的方法是什么？

Question

我需要为文件和文件夹排序 8145 个对象(可能还有更多)。 (在 A8X 上测试)。

第一种方法。

for(NSString *filename in FilesList) //This method takes an average of 7.7 seconds.
{
    fileExtension = (__bridge CFStringRef)[filename pathExtension];
    fileUTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, fileExtension, NULL);
    if ([­[­[­[NSFileManager defaultManager] attributesOfItemAtPath:[FolderPath stringByAppendingPathComponent:filename] error:nil] fileType] isEqualToString:@"NSFileTypeDirectory"] && !UTTypeConformsTo(fileUTI, kUTTypeRTFD))
       [OnlyFolderList addObject:filename];
    else
       [OnlyFilesList addObject:filename];
}

第二种方法。

for(NSString *filename in FilesList) //This method takes an average of 2.9 seconds.
{
     fileExtension = (__bridge CFStringRef)[filename pathExtension];
     fileUTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, fileExtension, NULL);
      [[NSFileManager defaultManager] fileExistsAtPath:[FolderPath stringByAppendingPathComponent:filename] isDirectory:&isDir];
      if (isDir && !UTTypeConformsTo(fileUTI, kUTTypeRTFD))
          [OnlyFolderList addObject:filename];
      else
          [OnlyFilesList addObject:filename];
}

你知道更快的方法吗？

-----用添加最快的方法更新-----//8145 个对象用时 0.26 秒!

    NSNumber *isDirectory;
    NSError *error = nil;
    NSString *name;
    NSArray *FilesList = [[NSFileManager defaultManager] contentsOfDirectoryAtURL:[NSURL fileURLWithPath:FolderPath] includingPropertiesForKeys:[NSArray arrayWithObjects:NSURLIsDirectoryKey,NSURLNameKey,nil] options:NSDirectoryEnumerationSkipsHiddenFiles error:nil];
    for (NSURL *url in FilesList)
    {
       [url getResourceValue:&name forKey:NSURLNameKey error:&error];
       [url getResourceValue:&isDirectory forKey:NSURLIsDirectoryKey error:&error];
       if ([isDirectory boolValue])
       {
           CFStringRef fileExtension = (__bridge CFStringRef)[name pathExtension];
           CFStringRef fileUTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, fileExtension, NULL);
           if (!UTTypeConformsTo(fileUTI, kUTTypeRTFD))
               [OnlyFolderList addObject:name];
           else
               [OnlyFilesList addObject:name];
       }
       else
           [OnlyFilesList addObject:name];
    }

Answer 1

尝试使用 contentsOfDirectoryAtURL:includingPropertiesForKeys:options:error::

NSURL *root = ... // the root URL to get the file list from
NSFileManager *fm = [NSFileManager defaultManager];
NSError *error = nil;
NSArray *filesList = [fm contentsOfDirectoryAtURL:root includingPropertiesForKeys:@[ NSURLIsDirectoryKey, NSURLTypeIdentifierKey ] options:NSDirectoryEnumerationSkipsHiddenFiles error:&error];
if (dirURLs) {
    for (NSURL *fileURL in filesList) {
        NSString *filename = [[fileURL path] lastPathComponent];
        NSNumber *isDir = nil;
        [fileURL getResourceValue:&isDir forKey:NSURLIsDirectoryKey error:nil]
        if ([isDir boolValue]) {
            NSString *uti;
            [fileURL getResourceValue:&uti forKey:NSURLTypeIdentifierKey error:nil];
            if ([(__bridge NSString *)kUTTypeRTFD isEqualToString:uti]) {
                [OnlyFilesList addObject:filename];
            } else {
                [OnlyFoldersList addObject:filename];
            }
        } else {
            [OnlyFilesList addObject:filename];
        }
    }
} else {
    NSLog(@"Unable to get list of files in %@: %@", root, error);
}