关于System.IO.Compression.GZipStream的使用

       //添加引用

          using System.IO.Compression;

           //压缩数组
        public unsafe static byte[] Compress(byte[] data)
        {
            MemoryStream ms = new MemoryStream();
            Stream zipStream = new GZipStream(ms, CompressionMode.Compress, true);
            zipStream.Write(data, 0, data.Length);
            zipStream.Close();


            byte[] newByteArray = new byte[ms.Length];

            ms.Seek(0, SeekOrigin.Begin);
            ms.Read(newByteArray, 0, newByteArray.Length);

            //zipStream.Write(buffer, 0, buffer.Length);
            //zipStream.Read(newByteArray, 0, (int)ms.Length);


            return newByteArray;
        }
        //解压缩数组
        public unsafe static byte[] DeCompress(byte[] data)
        {
            MemoryStream ms = new MemoryStream();

            ms.Write(data, 0, data.Length);
            ms.Seek(0, SeekOrigin.Begin);

            Stream zipStream = new GZipStream(ms, CompressionMode.Decompress,false);

            byte[] newByteArray = RetrieveBytesFromStream(zipStream, 1);
            return newByteArray;
        }
        public unsafe static byte[] RetrieveBytesFromStream(Stream stream, int bytesblock)
        {
            //---从一个流对象中检索字节---
            List<byte> lst = new List<byte>();
            byte[] data=new byte[2];
            int totalCount = 0;
            try
            {
                while (true)
                {
                    //'---逐渐地增加数据字节数组-的大小--
                    int bytesRead = stream.Read(data, totalCount, bytesblock);
                    if (bytesRead == 0)
                    {
                        break;
                    }
                    lst.Add(data[data.Length - 1]);
                    totalCount += bytesRead;
                    data = new byte[totalCount+1];
                }
                //'---确保字节数组正确包含提取的字节数---
                byte[]  data2 = new byte[totalCount];
                lst.CopyTo(data2, 0);
                
                
                return data2;
            }
            catch (Exception ex)
            {
                //MsgBox(ex.ToString)
                return new byte[0];
            }
        }

private void button1_Click(object sender, EventArgs e)
        {
            int len = 10*1024;
            byte[] data = new byte[len];
            Random rnd = new Random(255);
            for (int i = 0; i < len; i++)
            {
                data[i] = (byte)(int)(i/45);
            }

            int t1 = System.Environment.TickCount;
            byte[] data2 = Compress(data);

            //byte[] data3 = DeCompress(data2);
            int t2=System.Environment.TickCount;
            MessageBox.Show(string.Format("耗时 {0} 耗秒.压缩比{1}/{2}={3}", t2 - t1, data2.Length, data.Length, data2.Length*1.0/data.Length));
        }