We have a simple binary file format for caching data in our application (C# .NET Windows App). The format is basically a short that indicates the object type followed by a guid (string) for the object id then any object specific data (strings ints whatever). We want to be able to store many objects in the same file (> 10000) but in certain situations only load on demand. The solution we have is to keep an index of the object locations within the file – so when we start writing a new object we record the position in the file stream the object starts. When we want to load this object, we use this indexed location to load the relavent data. This works fine.
However, if we want to compress the file, will this method still be possible? I’m not too hot on how compression works and specifically the GZipStream class (System.IO.Compression) that we are planning to use. As I understand it, this class does not support Seeking or the Position property. Will it still be possible to use the Seek and Position of the underlying FileStream (I’m guessing not)? Basically, is it possible to have a compressed file that we can selectively load from, if so, how do we do it?
Thanks,
Steve
No, if you want to access a specific position in the uncompressed data you will have to decompress it, at least temporarily