文件压缩和解压 FileStream GZipStream

  using (FileStream reader=new FileStream (@"c:\1.txt",FileMode.Open,FileAccess.Read))
            {
                using (FileStream writer=new FileStream (@"c:\4.zp",FileMode.OpenOrCreate,FileAccess.Write))
                {
                    //压缩写的流
                    using (GZipStream zip=new GZipStream (writer,CompressionMode.Compress))
                    {
                        byte[] buffer = new byte[];
                        int r = ;
                        while ((r=reader.Read(buffer,,buffer.Length))>)
                        {
                            //压缩写入
                            zip.Write(buffer,,r);

                        }
                    }
                }
            }
            Console.WriteLine("/压缩完成");

            using (FileStream reader = new FileStream(@"c:\4.zp", FileMode.OpenOrCreate, FileAccess.Read))
            {
                using (FileStream writer = new FileStream(@"c:\5.txt", FileMode.OpenOrCreate, FileAccess.Write))
                {
                    byte[] buffer = new byte[];
                    //解压读的流 因读的是压缩文件，reader读出的是压缩后的流
                    using (GZipStream zip = new GZipStream(reader, CompressionMode.Decompress))
                    {
                        int r=;

                        while ((r = zip.Read(buffer, , buffer.Length)) > )
                        {
                            //正常的流写入
                            writer.Write(buffer, , r);
                        }
                    }

                }
            }

这种压缩只能实现单个文件的压缩和解压，多个文件的暂时不能使用