Best .NET Framework compression class?

Question

Hi all

Yes, I know GZipStream or DeflateStream is the common ones in .NET Framework which handle compression/decompression.

I wish to have compress/decompress functions in my program, but

1. I wish a .NET Framework C# one, not a 3rd party open source. I can't use because of those copyright restrictions in my program.

2. GZipStream and DeflateStream are not so good. for e.g., GZipStream compress a file to 480KB while 7Zip compress the same file to the size of 57KB.

Does Microsoft have other good compression methods???

Thanks

Answer 1

GZipStream and DeflateStream are specifically intended for compressed streams, not general compression of files for storage.

Other than those classes, compression is not built into .NET. If you want high-quality compression you will have to go to a third party library. Check out http://www.7-zip.org/sdk.html for an open-source 7zip library.

Answer 2

I don't have any statistics regarding compression rates, but I'd been using the SharpZipLib library for years with much success.

Answer 3

There is a managed wrapper for 7zip. The license is LGPL so you can use it in closed source projects. I do not know if this fits your license requirements as you did not state them.

http://sevenzipsharp.codeplex.com/

Answer 4

you can also use the open source ZLib (http://www.zlib.net/) with PInvoke, or use a wrapper for it (I've used zlib.net - http://www.componentace.com/zlib_.NET.htm - but I believe it had some bugs). it's less convenient than managed libraries, but more efficient than DeflateStream/GZipStream (which are the same except for an extra CRC in GZipStream).