public SimpleArchiveFileSystem(string filename)
{
if (!File.Exists(filename))
{
CreateArchive(filename);
}
stream = new FileStream(filename, FileMode.Open);
BinaryReader br = new BinaryReader(stream);
header = new FileHeader();
header.Read(br);
br.BaseStream.Position = header.FileIndexOffset;
fileIndex = new FileIndex();
fileIndex.Read(br);
br.BaseStream.Position = header.FolderIndexOffset;
folderIndex = new FolderIndex();
folderIndex.Read(br);
}