压缩解压函数实现

private byte[] Compression(byte[] data, CompressionMode mode)
        {
            DeflateStream zip = null;
            try
            {
                if (mode == CompressionMode.Compress)//压缩函数
                {
                    MemoryStream ms = new MemoryStream();
                    zip = new DeflateStream(ms, mode, true);
                    zip.Write(data, 0, data.Length);
                    zip.Close();
                    return ms.ToArray();
                }
                else//解压函数
                {
                    MemoryStream ms = new MemoryStream();
                    ms.Write(data, 0, data.Length);
                    ms.Flush();
                    ms.Position = 0;
                    zip = new DeflateStream(ms, mode, true);
                    MemoryStream os = new MemoryStream();
                    int SIZE = 1024*100;
                    byte[] buf = new byte[SIZE];
                    int l = 0;
                    do
                    {
                        l = zip.Read(buf, 0, SIZE);
                        if (l == 0) l = zip.Read(buf, 0, SIZE);
                        os.Write(buf, 0, l);
                    } while (l != 0);
                    zip.Close();
                    return os.ToArray();
                }
            }
            catch
            {
                if (zip != null) zip.Close();
                return null;
            }
            finally
            {
                if (zip != null) zip.Close();
            }
        }