遍历文件夹下某种某种所有文件类型

- (NSArray*) allFilesAtPath:(NSString*) dirString {
    NSMutableArray* array = [NSMutableArray array];
    //文件操作对象
    NSFileManager *manager = [NSFileManager defaultManager];
    //文件夹路径
    NSString *home = [dirString stringByExpandingTildeInPath];//根目录文件夹
    //目录迭代器
    NSDirectoryEnumerator *direnum = [manager enumeratorAtPath:home];
    //新建数组，存放各个文件路径
    NSMutableArray *files = [NSMutableArray arrayWithCapacity:42];
    //遍历目录迭代器，获取各个文件路径
    NSString *filename;
    while (filename = [direnum nextObject]) {
        if ([[filename pathExtension] isEqualTo:@"htm"]) {//筛选出文件后缀名是htm的文件
            [files addObject:filename];
        }
    }
    NSLog(@"%lu",[files count]);
    //遍历数组，输出列表
    NSEnumerator *enume = [files objectEnumerator];
    while (filename = [enume nextObject]) {
        [array addObject:filename];
    }
    return array;
}