Ch2, lesson3 - Compressing Streams.

• save space or bandwidth by compressing data.
• I/O system - 2 mthds for compressing data: GZIP, DEFLATE.
• both mthds - lmtd to compress 4GB of uncompressed data.
• GZipStream, DeflateStream classes.
• GZipStream Vs DeflateStream - GZIP has header. Header might be useful when decrompressing with gzip tool. If internal - DeflateStream file slightly smaller. If external - gzip, as may need header.
• CompressionStreams - write to another stream, not a resource (e.g. a file or memory).
• CompressionStream - wraps the stream that contains (or will contain) compressed data.
• 1. Open file to be compressed + file to be written to - FileStream sourceFile = File.OpenRead(inFileName);
• 2. wrap outgoing stream - GZipStream compStream = new GZipStream(destFile, CompressionMode.Compress);
• 3. read data from source & feed -> compression stream -
• int theByte = sourceFile.ReadByte();
• while (theByte != -1)
• {
• compStream.WriteByte.((byte)theByte);
• theByte = sourceFile.ReadByte();
• }